The purpose of the study was to design a rehabilitation program using hatha yoga exercises to improve knock knees for preschool children under research. The researcher used the semi-experimental method using the pre and post measurement for one experimental group on a sample selected intentionally of (18) children with knock knees of practitioners of gymnastics in schools (Ibn Khaldoun, AL-Haditha, Huda Shaarawi) in Benha city at Qalyubia governorate with a percentage of 64.3 % of the research community of (14) children who are the basic sample of the research and four children who are the members of the survey sample of the research. The research results have shown that the positive effect of the rehabilitation program using hatha yoga exercises has led to an improvement in the (variables of the electromyography of knock knees to make muscular balance between the muscles of the medialis side and the muscles of the lateral side of the knee joint & physical and postural variables of knock knees) for the sample under research.The researcher recommends the need to apply the rehabilitation program using hatha yoga exercises under consideration on the preschool children with knock knees as well as a series of preventive measures to preserve the postural status for preschool children.