Introduction: CITATION is an essential prevalent feature of all academic writings in various fields of knowledge. It is employed by authors and researchers across disciplines for diverse reasons. This study was aimed at comparing TYPEs and functions of CITATIONs in medical research articles in discussion sections between Iranian medical faculty members and their native counterparts.Method: To this end, discussion sections of 48 native and non-native written Research Articles (RAs) from credible ISI-indexed journals with good impact factor (about 0.5-1.5) from each group were analyzed in terms of CITATION TYPEs and functions.Results: The results revealed that non-integral CITATIONs were found to be the most frequent CITATION TYPE both among RAs written by non-native and native researchers. Also, Vancouver referencing style in non-native articles was used more while in native articles APA referencing style was the dominant style. Concerning CITATION functions, referencing was the most common one in native articles. However, referencing and comparisons were the most two frequent functions among non-native articles. As the results revealed, there were striking differences in CITATION practices of native and non-native researchers in medical sciences.Conclusion: This study calls for reevaluation of CITATION practices among Iranian authors and systematic treatment of TYPEs and functions of CITATIONs in ESM and EAP writing courses.