The purpose of this study was to investigate the effects of regular stretching program upon the development of physical flexibility and power of elementary school students with mental retardation in a special school and to provide the fundamental data as an warming up during the physical education class in the field. 30 students in a special school who composed of 14 special school students and 16 inclusive class in regular school students, who are mainly identificated as metal retardation and emotional disorder, participated in the program. Experiment procedures were taken pre-test, implementation of the program and post-test, each session lasted for 20 minutes per every weeks and 30 sessions in total were conducted at the environment of a special school. To verify effects between the experimental group and the control group, the pretest scores of two groups was used with SPSS/PC as a covariate variable. The difference of pre and post-test scores regarding two group were verified using MANOVA. This study found that below. Firstly, there was a significant positive effects of the regular stretching program upon the development of physical flexibility and power of experimental group and especially inclusive class student group was much more than special school student group. Secondly, according as gender, there was significant effect both gender especially male students\' development of basic training of Standing Long Jump. Thirdly, according as kinds of disability, there was positive effects of mental retardation and emotional disorders group students *Key words : Stretching program, Mental retardation, emotional disorder