This paper proposes the design and implementation of the education-oriented μITRON4.0 specification operating system on 8-bit PIC microcontrollers. In order to execute multi-task operatings in their small-capacity memories, we have adopted a shared stack structure. The primary purpose of our system development is to get an effective teaching material for RTOS educations in our university, so that students can easily understand the dynamics and mechanism of μITRON. Therefore, we have constructed a low-cost training environment with enough logging and debugging capabilities for the multi-task operation analysis in itself. In addition, we have developed the lessons that utilize this system listed as follows : “Practice of Embedded Software” and “Retraining of vocational training instructor”. Their questionnairy results answered by these students show positive evaluations in average for all lessons, which lead to the educational effectiveness of our system.