To address the complex challenges of modern new energy vehicles, such as low network transmission latency and high real-time data requirements, a vehicle gateway controller based on CAN FD (Controller Area Network Flexible Data-rate) was designed using Renesas automotive-grade microcontroller RH850/F1K. It features six bus channels, supports both classical CAN and CAN FD, and includes data storage functionality. The bus transceiver employs the next-generation CAN transceiver TJA1462 to enhance signal transmission performance. The software design is based on the embedded operating system FreeRTOS, enabling multitasking and structured hierarchical functions. Additionally, a specialized driver was developed for the CAN peripheral's unique transceiver method on the RH850/F1K microcontroller. Using a USB-to-CAN tool, the gateway's data transmission and storage capabilities were tested. The results demonstrate that the designed gateway controller can operate stably even when the load rate approaches the bus usage limit, providing an efficient and reliable solution for vehicle gateway controllers.