The aim of this study was to identify motivational and personality factors and to assess membership in volunteering and socialization factors in sport volunteers. This study was of a descriptive field nature. The population consisted of 260 sport volunteers in sport association of Fars province. 74 subjects were selected as the sample by cluster sampling. Questionnaire of motivation of volunteers by Liat Kulik (2007), Questionnaire of Ten Item Personality Inventory (TIPI) by Gosling, Rentfrow and Swann (2003) and the researcher-made questionnaire of social effect and demographic questionnaire were used to collect data. Sport management and psychology professors confirmed the validity of the questionnaires and the reliability of the questionnaires were determined as r=0.81, 0.82, 0.81) (?=0.05) in a pilot study. The collected data were analyzed by descriptive and inferential statistics such as Pearson correlation coefficient. The findings showed that family support was the most important and appreciation was the least important factor in volunteers. Most volunteers were extraverts. Females gained higher mean scores in all three factors of social effect than men did. There was a significant relationship between religion and social effect. There was no significant relationship between empowerment and appreciation with all the other variables. There was a significant relationship between respect for rules and regulations with agreeableness and extraversion. It is suggested that if managers can combine recreation and voluntary work, motivation of volunteers will improve and good citizenship and economic benefits will increase.