Increasing the performance of the health workers who working labour-intensive sector is important both in terms of ensuring the promotion of service quality and patient satisfaction and achieving the organizational goals. Positive psychological capital that is one of the growing areas of organizational behavior at the individual level is seen as a psychological resource that can stimulate growth and performance. Raising the levels of psychological capital of health worker can be effective in increasing the efficiency and performance required of them. The aim of this research is to investigate the effects of psychological capital on performance of employees. As data collection tool was used the Psychological Capital Questionnaire and the Employee Performance Scale. The research was applied to the 152 health professionals working in administrative and clinical units of a public hospital. The findings of the study indicated that that there was a statistically significant positive correlation in the medium level between psychological capital (r=0.685, p<0.001) and employee performance and with all the dimensions of psychological capital (self-efficacy, hope, optimism and resiliency) explained the 47% of variance of employee performance