Background: Indentifying influential factors on the wellbeing of health personnel plays a significant role in the promotion of effectiveness and outcomes of health systems. This study aimed to determine the awareness, attitude and performance of nurses regarding principles of universal precautions. Methods: In this cross-sectional study, the data were obtained through a questionnaire. The study sample was all of the nurses at Zabol, Iran, hospitals in 2010. Validity and reliability of the questionnaire was approved in a pilot study. Knowledge, attitude and performance scores were categorized as weak, average and good. Data were analyzed through descriptive statistics, Student’s t, chi-square and Fisher’s exact test. Results: The mean awareness score of 39.1% of the nurses was average, and of the rest (60.9%) was good. The attitude score of 10.4% of nurses was average and 89.6% had a good attitude toward comprehensive precautionary principles. The performance score was weak in 13.9%, average in 68.7%, and satisfactory in only 17.4% of the nurses. There was no significant relationship between age, gender and work experiences with awareness, attitude and performance of nurses; but, there was a significant relationship (P < 0.05) between performance and the serving hospitals. Conclusions: Despite good awareness and attitude of nurses regarding comprehensive precautionary principles, their performance was weak. So, official’s attention should become more in performing training classes and continuous educational courses.