Background & Aim: Knowledge of nursing is necessary for caring people suffering from pain. Regarding pain management and nursing role in order to put into practice exact pain management and availing comfort, possessing knowledge and positive attitude toward nursing care in this population have an important role.

Methods & Materials: This descriptive (cross- sectional study) determines cancer nurses knowledge and attitudes regarding pain management in hospitalized patients in related wards in Tehran University of medical sciences. Total of 113 nurses (from 132 questionnaires were sent, 113 of them were completed) who work in cancer wards in Tehran University of medical science hospitals were selected by convenience sampling (accidental sampling). For data gathering, questionnaires were used. Statistical analysis was performed using 2 test, t-test and Pearson correlation coefficient. To compare results and for describing the results, descriptive analysis were used. Results:

Results indicates that knowledge and attitude of samples is in a high school (level of knowledge 76% and level of attitude 86.6%). The correlation between knowledge and attitudes is (R=0.350), (p=0.000) that means there is a direct relation between nurses knowledge and attitudes and by increasing one of them، the other will increase.

Conclusion: Some of features like level of education, taking part in continuing education, working in chemotherapy and radiotherapy ward, operating room and facing to cancer patients, influence on nurses knowledge and attitudes.