Background and Objective : Nursing is an extremely stressful profession. Nurses are confronted with a variety of personal, communicational and organizational stresses, which affect on their health and job satisfaction reversely. The purpose of present study is to determine nurse's job stress in therapeutic-educational centers in Zanjan.

  Material and Methods : In this cross sectional descriptive- analytical study 155 nurses of nursing staff of teaching hospitals of Zanjan were selected by stratified random sampling in 2010. The instruments were a demographic data sheet and Toft-Gray and Anderson's nursing stress scale. The Data were analyzed by SPSS-­14.5 software, using descriptive statistics and Spearman & Pearson correlation coefficient.

  Results: The results show that various occupational conditions lead to tensions, high level (57.4%), moderate (40%) and low intention (2.6 %). Based on Spearman, there is a significant relationship between levels of tension and education status (r= 0.192, P= 0.017). Other variables such as age, sex, ward, marital status, shift working, record of services, overtime and number of children show no significant relationship with occupational stress.

  Conclusion: Regarding to the harmful effect of occupational stress on nursing staff, we recommend that the authorities to consider reducing the stressful factors such as dissatisfaction of salary and premium, job overload, ambiguous roles and lack of social support.