TOPPERS Project is to develop a series of open source real time operating systems(RTOS) and other software stacks for embedded systems, also is one of the latest developments of ITRON specification, which is de-facto standard real time kernel specification in Japan. TOPPERS/ASP kernel is the core and foundation of TOPPERS Project, also is an exploration and protype of next generation RTOS. This paper makes a performance evaluation between TOPPERS/ASP kernel and other three well-known RTOSs, RTEMS, FreeRTOS, and μC/OS-II. By comparison in performance, the validity in design and features of TOPPERS/ASP kernel can be testified and presented.