The aim of the study is to examine the team cohesion and self-efficacy levels of volleyball referees. The research group includes a total of 280 volleyball referees, 138 female and 142 male, affiliated with the Turkish Volleyball Federation for the 2022-2023 volleyball season. "Personal Information Form", "Referee Self-Efficacy Scale" and "Group Environment Questionnaire" were used to collect data in the study. SPSS 24.0 program was used in the analysis of the research data. Independent sample t test and anova test were applied as statistical methods and p<0,05 significance level was taken. According to the findings, a change was found in the sub-dimensions of task integrity and task attractiveness of the group in terms of gender variable. Again, a difference was found in the social integration of the group and task integration of the group according to the years of refereeing. There was a difference in the self-efficacy levels of the referees according to the year of refereeing. A difference was found in the task integration dimension of the group according to the refereeing level. As a result, it was determined that as the experience of volleyball referees increased, their self-efficacy levels increased and as their refereeing levels increased, their task integration levels increased.