This study aims to investigate the influence of differences in sport events (individual event and group events) and three types of need (competence, autonomy, and relatedness) on motivation and further to explore the reasons for the lack of motivation. The experiment, which lasts 8 weeks, was conducted between the roller-skating class and basketball class, under the condition of the task mastery atmosphere. The results show that the task mastery atmosphere helps students to improve the intrinsic motivation in physical education learning (P.E. learning). Sport events have no significant effects on the motivation in physical education learning. The satisfaction of competence needs is more important in the environment of autonomous learning. The needs of autonomy, relatedness, and competence are the intermediary variables which influence the motivation level, interests, and efforts in physical education learning. The group event is helpful to improve the students' relatedness. The common action of high relatedness, high autonomy and high competence can improve the effort of physical education learning.