Purpose of the present study is to find out the effects of yogasanas and gymnastic activities on self-concept among school boys. The Investigator have also made an attempt to asscess the superiority among the groups. One hundred and fifty (N=150) school boys of District Howrah, West Bengal State were randomly selected as subjects for the present study. The age limit of the subjects was 10-12 years. All the subjects were divided into three equal groups such as Gr. Y (n=50), Gr. G (n=50) and Gr. C (n=50). Gr. Y and Gr. G were experimental groups and Gr. C was control group. Initially self-concept inventory scale was employed to all the subjects of each group and thereafter specific yogic treatment and gymnastic activities were given to Gr. Y and Gr. G respectively for four days in a week and continued the period of one year and finally the subjects were retested on criterion measures. The data were analyzed by t–ratio to find out the effects of the treatment. The investigator has also made an attempt to assess the superiority among experimental groups. The results of the study showed that Yogasanas and gymnastic activities were improved significantly at .05 level of confidence after one year treatment. Yogasanas was superior to gymnastic activities in self-concept of school boys.