In this paper, we propose the design of firmware (FW) update system for RTC-CANopen, including system structure and FW update algorithm. RTC-CANopen enables embedded and robotic systems to use existing CANopen device easily. We developed update algorithm and system based on the CANopen software update standard. Thus, our proposed system is able to support standard CANopen devices. By accomplishing our research, we can easily maintain the FW of embedded system as well as robotic system adopting RTC-CANopen.