The purposes of this research were: 1) to study organizational factors of Thai private university personnel 2) to study the level of stress of Thai private university personnel 3) to find a relationship between organizational factors and stress of Thai private university personnel and 4) to analyze organizational factors affecting stress of Thai private university personnel. The samples used in this study were 380 employees working in Thai private universities located in Bangkok. The research findings showed that organizational factors, in total, were perceived at high level. In particular, time management had the highest mean value, followed by work uncertainty, work load, co-worker relationship, and work condition. Stress of Thai private university personnel, in total, was perceived at high level. In particular, mental stress had the highest mean value, followed by physical stress and behavioral stress. Organizational factors were positively related to stress of Thai private university personnel at the statistical significance of 0.01 level, which workload had the highest relationship with stress of Thai private university personnel. Organizational factors had an effect on stress of Thai private university personnel at statistical significance of the .01 level. The organizational factors which had the highest effect on stress of Thai private university personnel were work uncertainty, followed by time management, workload, work condition, and co-worker relationship. The forecasting equation from the results of Multiple Regression Analysis can describe the effect of organizational factors on stress of Thai private university personnel at 74.5 percent (Adjust R2 =.745), whereas the rest 25.5 percent was the results of other variables which were not studied in this research.