Background: Patient safety is one of main indicators in quality control of health services. The most prevalent threatening cause of patient safety is medical errors especially medication errors. This study aimed at assessing the rate and type of nurses’ medication errors.

Materials and Methods: This study was a descriptive – analytical one which performed in a non-public hospital in East North Country. The studied hospital has 180 active beds in the fields such as general surgery, obstetrics and gynecology, infants, cardiology, angiography, CCU, ICU, and NICU. Due to limited population, all the nurses in the hospital (97 nurses) were participated in the study. The instrument was a self-designed questionnaire which was composed of two main parts (demographic data and medication errors information). Its reliability and validity was confirmed. Data were analyzed by SPSS software version 15 using t- test and ANOVA.

Results: Among the studied nurses, 76 nurses (78.3%) were female and 21 (21.7%) were male. The mean of age and work experience of participants were 29.3 and 8.7 respectively. The most frequent of medication errors included medication without prescription 136(23.7%), lack of attention to medical complications 134(23.4%), Giving the medication at the wrong time 128(22.4%). The lowest common of medication errors reported as using expired date medication4(0.7%), wrong medication 5(0.9%) and  non administered medication 6(1.1%).

Conclusion: The nursing managers should be consider more attention to reduce medication errors by implementing Training classes, improving nurse's processes and promoting attitudes towards importance of patient safety.