In such complex technological industry as constructions where contracts are estimated with million Euro budgets, where competition is fierce and penalties are high, it’s essential for contractors to ensure all management activities facilitate project success. Today many construction companies practice project management approach and employ project managers in charge of project success. This thesis aims to find out whether project manager’s leadership style has impact on construction project outcome, and if project managers should emphasize task-motivated or relationship-oriented leadership style in order to facilitate project success. As conducted theory review has shown there has been some prior research on leadership style impact on project outcome. Researchers have generally agreed that project manager’s leadership style is one of the project success’ factors. But studies of particular styles’ impact on construction project outcome mostly presented results with regard to transactional and transformational leadership which describe leader’s ability to cope with tasks when organizations are facing considerable change. However research lacks studies on task and relationship motivation of construction project managers. This study was conducted in order to fill in the blank in prior research and to provide basement for further studies. A sample of 24 Russian construction project managers was surveyed on their leadership style (task-motivated or relationship-oriented) and on success rate of construction projects completed by each respondent. Results have shown that there is moderate correlation between leadership style of construction project managers and that in order to facilitate construction project success, project managers should adhere to task accomplishment before establishing good interpersonal relationships with involved people. Findings of this study can be interesting both for researchers who are willing to further study impact of task-motivated leadership style on construction project success, and also for construction project owners/sponsors who hire project managers and for construction project managers themselves so that they could develop their leadership style in order to improve their projects’ success rate.