In this research, the mentally-handicapped children being able to be trained were investigated the actual condition of train function making 40 mentally-handicapped children in Kummi Hyedang Spacial Education School, to exmine the effect of physical exercise function when training the mentally-handicapped children who can be trained as applying exercise education programs, and trains for 10 weeks by assigning to both experiment group and control group according to children who are similar to training functions from pre-examination. The results are in following: First, the results of test in the exercise ability of mentally-handicapped children with the degree of being able to trained are very delayed in comparison with normal mental children through the both top and bottom examination. The developments of 5 exercise functions classified by domain, have the order of eyesight exercise, softness, physical strength, quickness, parallelism, the interaction of both eye and hand, and, have the exercise function being equal to the level of between 6 and 12 years old. In 13 bottom test, throwing bean-bag is equal to the nomal 12 years old boy. the board jump, sitting position / bending forward / closing are equal to the level of 12 years old boy. standing with only leg is the level of 9 years old, threading pearls is 7 years old, transfering the wood building, picking the upper body up, walking board, balancing one leg with opened, eye, fist / opening palm / palm, bending and opening arm with postrating on chair, are the exercise functions of below 6 years old. Second, there are great effects in carrying out the exercise education program to the mentally-handicapped children with the level of being able to trained. In experiment group, it is elevated to the middle level of 12 years old nomal children. Classified by domain of test the board jump, training, the bean-bag are far higher level than 12 years old normal children, and are elevated the level of 11 years old boy. Balancing only leg with closed eye is below the level of 10 years old boys, fist / opening palm / palm are the level of 9 years old boys. There and back running, picking the upper body is the level of 9 years old girls. Walking board is the level of 8 years old boys. Bending and opening arm with postrating on chair is the level of 7 rears old boy. Balancing one leg with opened eye is elevated to the level of f years old girls. These functions have the more balanced exercise function rather than pre-examination. In control group, they have little change by classified the bottom test, but have the exercise function on the time of pre-examination, go backward in physical strength. quickness. Third, the exercise function being learned by exercise education program on the mentally-handicapped children of the level with being able to train is appeared to maintain continuately. Softness, physical strength, quickness, eyesight training are maintained the learned exercise function, the interaction of both eye and hands, parallelism are delayed a little. Classified by the bottom test. threading pearls, transfering the wood building, throwing the bean-bag, sitting position / rolling forward / reaching, the broad jump and picking upper body up, there and bark running, picking upper body up, balancing with only leg as opened eye, bending and opening arm with postrating on chair, etc. are maintained. Fist / opening palm / palm, balancing with only leg as opened eye are delayed a little. The change of body position is elevated. Seeing these results, it is appeared to the mentally-handicapped children that the exercise education programs, which is suitable their actual condition and acomplishes in voluntary participation, have very positive effect. So, to develop the function of body exercise in mentally-handicapped children with the level of being to able to be trained, the measures must be groped so that the exercise education programs can be practiced positively, and the ,body exercise can be experienced more.