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The purpose of the present study was to determinethe effect of coaching behaviors on coaching efficacy and team dynamic of vollyball pro- league in Iran (2009). 160 athletes and coach from 13 team participated as samples in this study. Coacing behavior was measured by Martin, S.B., & Barnes, K. (1999) Coaching Behavior questionnaire. Coaching Efficacy was measured by Feltz, D.L., Chase, M.A, Mortiz, S.A., Sullivan, P.J. (1999) coaching efficacyquestionnaire. Team Dynamic (team cohesion and collective efficacy), was measured by Carron, A.V., Brawely, L., Widmeyer, W. (1998) team cohesion questionnaire and Felts, D.L., & Lirg, C.D., (1998) collective efficacy questionnaire. The statistical procedure also was based on descriptive and inferential basis and included multivariable regression. The results indicated that coaching behaviors effect on coaching efficacy and team dynamic. Also coaching efficacy effect on team dynamic. As the results revealed, higher frequency of Reinforcement, Mistake – Contingent technical instruction, General communication and organizing behaviors styles, showed an increase in coaching efficacy and team dynamic( team cohesion and collective efficacy) over the season. On the other hand, higher frequency Punishment and Punitive technical instruction behaviors style, an decrease in coaching efficacy and team dynamic ( team cohesion and collective efficacy) over the season.