The purpose of this study is to explore effects of team enablers (team autonomy and organizational support) and team cohesion dimensions on project team success and the mediating effect of team cohesion dimensions in this relation. Partial Least Squares Structural Equation Model (PLS-SEM) was used in the study conducted on 110 project teams which had 343 team members in a multinational financial institution. Reliability of the measures were calculated by Cronbach Alpha (?) coefficient and validity of the measures were calculated by exploratory and confirmatory factor analyses. As the unit of analysis is “project team”, the question items were aggregated to team level by calculating the arithmetic mean and inter-rater agreement values (rwg) were checked for reliability. The findings of the research revealed that organizational support was a significant antecedent of team task cohesion and team effectiveness. Team task cohesion was found to have a partial mediating role in the relationship between organizational support and team effectiveness. In addition, although the significant positive effects of team autonomy on project team success dimensions were confirmed, none of the dimensions of team cohesion had a significant relationship with team autonomy. In accordance with the literature, positive effects of task cohesion on team effectiveness and team innovation were supported, however the effect of social cohesion on project team success was not significant.