Abstarct: Technological advannces in modern life have made changes in lifestyle, causing such results as motor deficiency and increased risk of diseases. Studies have shown that exercise and especially entertaining sports for all as a means of cheap and bracing activity can help solving this problem. Due to the fact that the women’s participation in sports activities is one of the most important ways to providing their physical and mental health, it is essential to examine their presence reasons in sport and increase of their motivation as a key to start training, and their commitment to sports activities as a tool to continue training for more extended participation. The purpose of this study was to investigation participation motives and sport commitment among women participating in sports, this study was conducted in descxriptive and correlational method and statistical population study was conducted among 6000 women that participating in sports in Mashhad municipality. As a fact, the much larger sample size in structural equation modeling method, the more accurate and precise the results are, 526 samples were selected by cluster random from different areas of Mashhad. Data were collected by, demographic, sport motivation (the questionnaire made by researcher), and sport commitment (scanlan, 1993) questionnaires. To determine the Face and content validity of the questionnaires, 10 experts and sports management teachers were consulted and to determine the structural validity of the questionnaires, Confirmatory factor analysis were applied. Then to determine the reliability of sports motivation and sports commitment questionnaires, a pilot study on 30 women athletes was conducted. The results of cronbach's alpha coefficient showed (Sports motivation α=0.87) (Sport commitment α=0.64) that the questionnaires have acceptable reliability. The results showed that there is a positive and meaningful relationship between sports commitment and the subscales of intrinsic motivation and also between sports commitment and the subscales of extrinsic motivation. A positive and strong relationship between intrinsic motivation and extrinsic motivation (r=0.79) was observed. Structural equation modeling results indicated that intrinsic motivation had a direct effect on the sports commitment (0.67), but the effect of extrinsic motivation on the sports commitment was unmeaningful (-0.06). The coefficient of the endogenous variable, indicated that there is 39% variance in sports commitment can be predicted by exogenous variables. Finally, the model showed a good fit to the data.