This research aims at investigating the effect of THRPs(Therapeutic Horse Riding Programs) on the advancement of self-expressions and social skills of children with intellectual disabilities. The subjects of this investigation are six children with intellectual disabilities who are willing to participate in THRPs chosen among the special school students and special class in the regular school located in city of Y. To attain the object of the research I set up the research problems below: first, do THRPs improve the self-expression of children with intellectual disabilities? second, do THRPs elevate the social skills of children with intellectual disabilities? I had done this program once a week each 60 minutes from September to December, 2014, making a total of twelve sessions. After this investigation I conclude that THRPs are effective in the advancement of self-expressions and social skills of children with intellectual disabilities even though the size of sample is small that it would be difficult to generalize the outcome of programs. Therefore it is expected that THRPs will be helpful to the psychosocial adjustment.