I. Problem. This study is one of the action-research projects of the development of student baseball team activities in Kyushu University. The purpose of this study is to analyse their interpersonal relations and to make develop the human relations in team activities. II. Subjects. Subjects are 16 members of baseball team in Kyushu University. They need not always to have special ability for baseball. The team is composed of those who want to play baseball, even if their ability isnot specially fitted to it. III. Ist Experiment ; Study of the relationship between the individual motor fitness and ability of sociol adjustment. (1) Motor fitness and ability of baseball. The general motor fitness test was given to 14 members. The test consists of six factors, namely, strength, power, ability, flexibility, endurance and balance. The rank order from the first to the four-teenth was made by the results of this test. At the some time, the batting rank order was made bythe batting achievement of last year. The rank correlation between the order of motor ability and batting order was 0.174 except one who was the 12th in the motor fitness and the 3rd in the batting order-a very hard worker and a typical overachiever. By the results of questionair which was conducted to the members particlpating in the first camp training this year, it was found : (a) During five days of the camp training 63% of all members felt the existence of the cohesiveness of the group as a whole. (b) Some 80% of all members began to have friendship each other. (c) Some 70% became awars of the progress of their achie ement. (d) 54% suffered from conflicts between the academic studies and team activities.