The author of this article utilizes social facilitation theory in social psychology to probe into the issue of the movement ability displayed in sports competition,discusses the factors which affect the function of social facilitation in sports and analyzes the different degrees displayed by social facilitation with different projects or different proficiency of athletes for the same project,as well as the different effects of social facilitation displayed with the different significance of the athletes perceiving valuators.A special case of social facilitation-gender facilitation displayed in movement ability is also discussed in the paper.