diff --git a/README.md b/README.md
index b9068a4968..e6915dbc24 100644
--- a/README.md
+++ b/README.md
@@ -819,6 +819,7 @@ User can add a STM32 based board following this [wiki](https://github.com/stm32d
| :----: | :-------: | ---- | :-----: | :---- |
| :green_heart: | STM32WB15CCU | Generic Board | *2.5.0* | |
| :green_heart: | STM32WB55CC
STM32WB55CE
STM32WB55CG | Generic Board | *2.0.0* | |
+| :yellow_heart: | STM32WB55CGU | [WeAct STM32WB55CGU6](https://github.com/WeActStudio/WeActStudio.STM32WB55CoreBoard) | **3.0.0** | |
| :green_heart: | STM32WB5MMG | Generic Board | *2.1.0* | |
| :green_heart: | STM32WB55RC
STM32WB55RE
STM32WB55RG | Generic Board | *2.0.0* | |
| :green_heart: | STM32WB55VC
STM32WB55VE
STM32WB55VG | Generic Board | *2.10.0* | |
diff --git a/boards.txt b/boards.txt
index 3bd0ec8e17..cb35b465ee 100644
--- a/boards.txt
+++ b/boards.txt
@@ -13539,6 +13539,16 @@ GenWB.openocd.target=stm32wbx
GenWB.vid.0=0x0483
GenWB.pid.0=0x5740
+# WeAct STM32WB55CGU6
+GenWB.menu.pnum.WEACT_WB55CGU6=WeAct STM32WB55CGU6
+GenWB.menu.pnum.WEACT_WB55CGU6.upload.maximum_size=524288
+GenWB.menu.pnum.WEACT_WB55CGU6.upload.maximum_data_size=196608
+GenWB.menu.pnum.WEACT_WB55CGU6.build.board=WEACT_WB55CGU6
+GenWB.menu.pnum.WEACT_WB55CGU6.build.product_line=STM32WB55xx
+GenWB.menu.pnum.WEACT_WB55CGU6.build.variant=STM32WBxx/WB35C(C-E)UxA_WB55C(C-E-G)U
+GenWB.menu.pnum.WEACT_WB55CGU6.build.variant_h=variant_WEACT_WB55CGU6.h
+GenWB.menu.pnum.WEACT_WB55CGU6.debug.svd_file={runtime.tools.STM32_SVD.path}/svd/STM32WBxx/STM32WB55_CM4.svd
+
# Generic WB15CCUx
GenWB.menu.pnum.GENERIC_WB15CCUX=Generic WB15CCUx
GenWB.menu.pnum.GENERIC_WB15CCUX.upload.maximum_size=131072
diff --git a/variants/STM32WBxx/WB35C(C-E)UxA_WB55C(C-E-G)U/CMakeLists.txt b/variants/STM32WBxx/WB35C(C-E)UxA_WB55C(C-E-G)U/CMakeLists.txt
index d432e3cb1a..f3ca131ed1 100644
--- a/variants/STM32WBxx/WB35C(C-E)UxA_WB55C(C-E-G)U/CMakeLists.txt
+++ b/variants/STM32WBxx/WB35C(C-E)UxA_WB55C(C-E-G)U/CMakeLists.txt
@@ -24,6 +24,7 @@ add_library(variant_bin STATIC EXCLUDE_FROM_ALL
variant_generic.cpp
variant_MKR_SHARKY.cpp
variant_P_NUCLEO_WB55_USB_DONGLE.cpp
+ variant_WEACT_WB55CGU6.cpp
)
target_link_libraries(variant_bin PUBLIC variant_usage)
diff --git a/variants/STM32WBxx/WB35C(C-E)UxA_WB55C(C-E-G)U/variant_WEACT_WB55CGU6.cpp b/variants/STM32WBxx/WB35C(C-E)UxA_WB55C(C-E-G)U/variant_WEACT_WB55CGU6.cpp
new file mode 100644
index 0000000000..89d12abb7b
--- /dev/null
+++ b/variants/STM32WBxx/WB35C(C-E)UxA_WB55C(C-E-G)U/variant_WEACT_WB55CGU6.cpp
@@ -0,0 +1,150 @@
+/*
+ *******************************************************************************
+ * Copyright (c) 2026, STMicroelectronics
+ * All rights reserved.
+ *
+ * This software component is licensed by ST under BSD 3-Clause license,
+ * the "License"; You may not use this file except in compliance with the
+ * License. You may obtain a copy of the License at:
+ * opensource.org/licenses/BSD-3-Clause
+ *
+ *******************************************************************************
+ */
+#if defined(ARDUINO_WEACT_WB55CGU6)
+#include "pins_arduino.h"
+#include "lock_resource.h"
+
+// Digital PinName array
+const PinName digitalPin[] = {
+ PB_2, // D0
+ PA_9, // D1
+ PA_8, // D2
+ PA_7, // D3
+ PA_6, // D4
+ PA_5, // D5
+ PA_4, // D6
+ PA_3, // D7
+ PA_2, // D8
+ PA_1, // D9
+ PA_0, // D10
+ PB_8, // D11
+ PB_9, // D12
+ PH_3, // D13 - BOOT0 / SW2 button
+ PB_0, // D14
+ PB_1, // D15
+ PE_4, // D16 - onboard blue LED
+ PA_10, // D17
+ PA_15, // D18
+ PB_3, // D19
+ PB_4, // D20
+ PB_5, // D21
+ PB_6, // D22
+ PB_7 // D23
+};
+
+// Analog (Ax) pin number array
+const pin_size_t analogInputPin[] = {
+ 10, // A0, PA0
+ 9, // A1, PA1
+ 8, // A2, PA2
+ 7, // A3, PA3
+ 6, // A4, PA4
+ 5, // A5, PA5
+ 4, // A6, PA6
+ 3, // A7, PA7
+ 2, // A8, PA8
+ 1 // A9, PA9
+};
+
+// ----------------------------------------------------------------------------
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief System Clock Configuration
+ * @param None
+ * @retval None
+ *
+ * Board is fitted with a 32MHz HSE crystal (X2) and a 32.768kHz LSE
+ * crystal (X1). SYSCLK is driven directly by HSE (no PLL needed) and
+ * USB/RNG are clocked from the dedicated HSI48 oscillator, otherwise
+ * the USB peripheral is left unclocked and never enumerates.
+ */
+WEAK void SystemClock_Config(void)
+{
+ RCC_OscInitTypeDef RCC_OscInitStruct = {};
+ RCC_ClkInitTypeDef RCC_ClkInitStruct = {};
+ RCC_PeriphCLKInitTypeDef PeriphClkInitStruct = {};
+
+ /* This prevents concurrent access to RCC registers by CPU2 (M0+) */
+ hsem_lock(CFG_HW_RCC_SEMID, HSEM_LOCK_DEFAULT_RETRY);
+
+ /* Macro to configure the PLL multiplication factor */
+ __HAL_RCC_PLL_PLLM_CONFIG(RCC_PLLM_DIV2);
+
+ /* Macro to configure the PLL clock source */
+ __HAL_RCC_PLL_PLLSOURCE_CONFIG(RCC_PLLSOURCE_HSE);
+
+ __HAL_RCC_LSEDRIVE_CONFIG(RCC_LSEDRIVE_MEDIUMHIGH);
+ /* Configure the main internal regulator output voltage */
+ __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
+
+ /* This prevents the CPU2 (M0+) to disable the HSI48 oscillator */
+ hsem_lock(CFG_HW_CLK48_CONFIG_SEMID, HSEM_LOCK_DEFAULT_RETRY);
+
+ /* Initializes the CPU, AHB and APB busses clocks */
+ RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI48 | RCC_OSCILLATORTYPE_HSI
+ | RCC_OSCILLATORTYPE_HSE | RCC_OSCILLATORTYPE_LSE;
+ RCC_OscInitStruct.HSEState = RCC_HSE_ON;
+ RCC_OscInitStruct.LSEState = RCC_LSE_ON;
+ RCC_OscInitStruct.HSIState = RCC_HSI_ON;
+ RCC_OscInitStruct.HSI48State = RCC_HSI48_ON;
+ RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
+ RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
+ if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
+ Error_Handler();
+ }
+
+ /* Configure the SYSCLKSource, HCLK, PCLK1 and PCLK2 clocks dividers */
+ RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK4 | RCC_CLOCKTYPE_HCLK2
+ | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_SYSCLK
+ | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2;
+ RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSE;
+ RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
+ RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
+ RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
+ RCC_ClkInitStruct.AHBCLK2Divider = RCC_SYSCLK_DIV1;
+ RCC_ClkInitStruct.AHBCLK4Divider = RCC_SYSCLK_DIV1;
+ if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1) != HAL_OK) {
+ Error_Handler();
+ }
+
+ /* Initializes the peripherals clocks */
+ /* RNG needs to be configured like in M0 core, i.e. with HSI48 */
+ PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_SMPS | RCC_PERIPHCLK_RFWAKEUP
+ | RCC_PERIPHCLK_RNG | RCC_PERIPHCLK_USB;
+ PeriphClkInitStruct.RFWakeUpClockSelection = RCC_RFWKPCLKSOURCE_LSE;
+ PeriphClkInitStruct.RngClockSelection = RCC_RNGCLKSOURCE_HSI48;
+ PeriphClkInitStruct.SmpsClockSelection = RCC_SMPSCLKSOURCE_HSE;
+ PeriphClkInitStruct.SmpsDivSelection = RCC_SMPSCLKDIV_RANGE0;
+ PeriphClkInitStruct.UsbClockSelection = RCC_USBCLKSOURCE_HSI48;
+
+ if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK) {
+ Error_Handler();
+ }
+
+ LL_PWR_SMPS_SetStartupCurrent(LL_PWR_SMPS_STARTUP_CURRENT_80MA);
+ LL_PWR_SMPS_SetOutputVoltageLevel(LL_PWR_SMPS_OUTPUT_VOLTAGE_1V40);
+ LL_PWR_SMPS_Enable();
+
+ /* Select HSI as system clock source after Wake Up from Stop mode */
+ LL_RCC_SetClkAfterWakeFromStop(LL_RCC_STOP_WAKEUPCLOCK_HSI);
+
+ hsem_unlock(CFG_HW_RCC_SEMID);
+}
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* ARDUINO_WEACT_WB55CGU6 */
diff --git a/variants/STM32WBxx/WB35C(C-E)UxA_WB55C(C-E-G)U/variant_WEACT_WB55CGU6.h b/variants/STM32WBxx/WB35C(C-E)UxA_WB55C(C-E-G)U/variant_WEACT_WB55CGU6.h
new file mode 100644
index 0000000000..a2764542cd
--- /dev/null
+++ b/variants/STM32WBxx/WB35C(C-E)UxA_WB55C(C-E-G)U/variant_WEACT_WB55CGU6.h
@@ -0,0 +1,150 @@
+/*
+ *******************************************************************************
+ * Copyright (c) 2026, STMicroelectronics
+ * All rights reserved.
+ *
+ * This software component is licensed by ST under BSD 3-Clause license,
+ * the "License"; You may not use this file except in compliance with the
+ * License. You may obtain a copy of the License at:
+ * opensource.org/licenses/BSD-3-Clause
+ *
+ *******************************************************************************
+ */
+#pragma once
+
+/*----------------------------------------------------------------------------
+ * STM32 pins number
+ *----------------------------------------------------------------------------*/
+#define PB2 0
+#define PA9 PIN_A9
+#define PA8 PIN_A8
+#define PA7 PIN_A7
+#define PA6 PIN_A6
+#define PA5 PIN_A5
+#define PA4 PIN_A4
+#define PA3 PIN_A3
+#define PA2 PIN_A2
+#define PA1 PIN_A1
+#define PA0 PIN_A0
+#define PB8 11
+#define PB9 12
+#define PH3 13 // BOOT0 / SW2 button
+#define PB0 14
+#define PB1 15
+#define PE4 16 // Onboard blue LED
+#define PA10 17
+#define PA15 18
+#define PB3 19
+#define PB4 20
+#define PB5 21
+#define PB6 22
+#define PB7 23
+
+// Alternate pins number
+#define PA7_ALT1 (PA7 | ALT1)
+#define PB8_ALT1 (PB8 | ALT1)
+#define PB9_ALT1 (PB9 | ALT1)
+
+#define NUM_DIGITAL_PINS 24
+#define NUM_ANALOG_INPUTS 10
+
+// On-board LED pin number
+#ifndef LED_BUILTIN
+ #define LED_BUILTIN PE4
+#endif
+
+// On-board user button (shared with BOOT0 hardware bootloader select)
+#ifndef USER_BTN
+ #define USER_BTN PH3
+#endif
+
+// SPI definitions
+#ifndef PIN_SPI_SS
+ #define PIN_SPI_SS PA4
+#endif
+#ifndef PIN_SPI_SS1
+ #define PIN_SPI_SS1 PA15
+#endif
+#ifndef PIN_SPI_SS2
+ #define PIN_SPI_SS2 PB2
+#endif
+#ifndef PIN_SPI_SS3
+ #define PIN_SPI_SS3 PNUM_NOT_DEFINED
+#endif
+#ifndef PIN_SPI_MOSI
+ #define PIN_SPI_MOSI PA7
+#endif
+#ifndef PIN_SPI_MISO
+ #define PIN_SPI_MISO PA6
+#endif
+#ifndef PIN_SPI_SCK
+ #define PIN_SPI_SCK PA5
+#endif
+
+// I2C definitions
+#ifndef PIN_WIRE_SDA
+ #define PIN_WIRE_SDA PB9
+#endif
+#ifndef PIN_WIRE_SCL
+ #define PIN_WIRE_SCL PB8
+#endif
+
+// Timer Definitions
+// Use TIM6/TIM7 when possible as servo and tone don't need GPIO output pin
+#ifndef TIMER_TONE
+ #define TIMER_TONE TIM16
+#endif
+#ifndef TIMER_SERVO
+ #define TIMER_SERVO TIM17
+#endif
+
+// UART Definitions
+#ifndef SERIAL_UART_INSTANCE
+ #define SERIAL_UART_INSTANCE 101
+#endif
+
+// Default pin used for generic 'Serial' instance
+// Mandatory for Firmata
+#ifndef PIN_SERIAL_RX
+ #define PIN_SERIAL_RX PA3
+#endif
+#ifndef PIN_SERIAL_TX
+ #define PIN_SERIAL_TX PA2
+#endif
+
+// Extra HAL modules
+#if !defined(HAL_QSPI_MODULE_DISABLED)
+ #define HAL_QSPI_MODULE_ENABLED
+#endif
+
+#ifndef HSE_VALUE
+ #define HSE_VALUE 32000000U
+#endif
+
+/*----------------------------------------------------------------------------
+ * Arduino objects - C++ only
+ *----------------------------------------------------------------------------*/
+
+#ifdef __cplusplus
+ // These serial port names are intended to allow libraries and architecture-neutral
+ // sketches to automatically default to the correct port name for a particular type
+ // of use. For example, a GPS module would normally connect to SERIAL_PORT_HARDWARE_OPEN,
+ // the first hardware serial port whose RX/TX pins are not dedicated to another use.
+ //
+ // SERIAL_PORT_MONITOR Port which normally prints to the Arduino Serial Monitor
+ //
+ // SERIAL_PORT_USBVIRTUAL Port which is USB virtual serial
+ //
+ // SERIAL_PORT_LINUXBRIDGE Port which connects to a Linux system via Bridge library
+ //
+ // SERIAL_PORT_HARDWARE Hardware serial port, physical RX & TX pins.
+ //
+ // SERIAL_PORT_HARDWARE_OPEN Hardware serial ports which are open for use. Their RX & TX
+ // pins are NOT connected to anything by default.
+ #ifndef SERIAL_PORT_MONITOR
+ #define SERIAL_PORT_MONITOR Serial
+ #endif
+ #ifndef SERIAL_PORT_HARDWARE
+ #define SERIAL_PORT_HARDWARE Serial
+ #endif
+#endif