© 2023 University of Ankara. All rights reserved.Objective: The genotypic analysis of the strains can provide information to evaluate the genetic relationships among strains and epidemiological investigations, and it is crucial for monitoring their circulation in different geographic regions. This study was to aim to identify genetic similarities or dissimilarities among clinical Acinetobacter baumannii (A. baumannii) isolates from four different hospitals. Material and Method: In this study, 78 non-duplicate clinical isolates of A. baumannii were received from patients in the critical care units. The colistin MIC values of 24 A. baumannii strains randomly selected from four different hospitals and known to have antibiotic susceptibility were determined. These strains were genetically characterized by the Enterobacterial repetitive intergenic consensus (ERIC)-PCR method. Result and Discussion: The results of the study showed that the isolates were divided into 2 clusters (A1 and A2) and Cluster A2 was represented by a single genotype (C1) and 23 interrelated genotypes were in Cluster A1.