Sports competition is one of the important contents and forms of sports activities and physical education. It plays a full range of valuable functions in promoting the all-round development of college students. Specifically, it can better help college students enjoy fun, enhance their physique, and improve their physical fitness during physical exercise. Personality and tempering the will. Countries around the world attach great importance to youth sports competitions, and use national strategies as the top-level design and sports events as activity carriers to create a series of youth sports competitions such as graded competitions, championships, and campus events, providing more opportunities for young people to watch and participate in sports. Opportunities and platforms for competition. College student sports competitions are an important part of youth sports competitions and shoulder multiple missions such as physical health promotion, competitive talent training, and sports industry development. In recent years, the development of college sports competitions around the world has achieved remarkable results, and the scale and quality of Chinese college sports competitions have also been significantly improved. However, compared with developed countries, overall, there is still a weak awareness of participation, poor competition experience, and competitive competition. Prominent problems such as low levels and high activity withdrawal rates have, to a certain extent, restricted the high-quality development of college student sports competitions. In fact, it is not as easy as imagined for college students to participate in sports competitions regularly for a long time. In addition to requiring college students to possess certain basic conditions such as time, energy, and skills, it also requires support and promotion from all walks of life, especially It is inseparable from the material, spiritual and technical support provided by family, friends, coaches and other important groups. Just as the social ecological model believes that individual physical activity behavior is closely related to social support at the interpersonal level, especially social support from important groups such as family and friends has a positive impact on individual physical activity behavior. At the same time, although social support is very important, not all social support received can promote college students to form good sports competition behaviors. Self-determination theory emphasizes that only effective social support can regulate and optimize individual sports motivation by meeting the individual’s basic psychological needs, and ultimately promote the formation of positive, long-term sports behavior. However, most of the current sports academic circles continue the research context of traditional college student sports management, focusing on the contemporary value, practical issues, system construction, etc. of college student sports competitions. They are more subjective qualitative theoretical research and relatively lack the influence of social support. Empirical research on the sports competition behavior of college students, so that the internal mechanism of social support affecting the sports competition behavior of college students is not clear enough and understood. Therefore, from the perspective of social ecology, this study explores the internal mechanism of social support affecting college students’ sports competition behavior, in order to provide certain theoretical reference for improving the level of college students’ sports competition behavior.

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