Abstarct: This study aimed to investigate the effect of group cohesion and motivation on the performance of team sports athletes in Shahrood city. The research method was applied in terms of purpose and descxriptive-correlational in terms of method, baxsed on structural equation modeling, and data collection was conducted in the field. The participants included all athletes in team sports in Shahrood city that using the convenience sampling method, 200 of these individuals were selected as a sample. To collect data, three questionnaires were used: group cohesion (Chin et al., 1999), motivation (Manouchehri et al., 2015), and performance (Glen et al., 2003). To confirm the face and content validity from the experts' point of view and to confirm the reliability of the instrument, Cronbach's alpha test was used, which was obtained as 0.81, 0.70, and 0.81 for group cohesion, motivation, and performance, respectively. Statistical analyses were performed using SPSS version 24 and SmartPLS version 3. Hypotheses were examined at a significance level of 0.05. The results of the study showed that group cohesion and motivation have a positive and significant effect on the performance of athletes in Shahrood (P<0.05). Therefore, the findings of this study can help coaches and sports managers to improve athletes' sports performance by creating more coordinated and cohesive team environments and increasing athletes' motivation. In addition, the present study provides a platform for future research on the interaction of psychological and group factors in sports.