<b>Objectives</b><br/> Brucellosis is the most common bacterial zoonosis in the world. Multilocus variable-number tandem-repeat (VNTR) analysis (MLVA) is a molecular method for genotyping bacterial species. <i>Brucella abortus</i> biovar I was isolated from most of the brucellosis-suspected patients in Korea. This study was conducted to investigate the ability of various MLVA primers that are used for molecular typing <i>B. abortus</i> isolates and for analyzing their epidemiological data.<br/><b>Methods</b><br/> A total of 80 human isolates of <i>B. abortus</i> biovar I isolated from human patients and the reference strain were used for MLVA. Genetic diversity was determined by calculating the Simpson's diversity index (DI) of each VNTR locus. The <i>Brucella</i> strains were subcultured 30 times to determine the stability of each locus. The DNA of the strains cultivated in each passage was extracted and subjected to MLVA for further investigation.<br/><b>Results</b><br/> The 15 VNTR loci were selected based on high DI values. The DIs of the 15 VNTR loci showed considerable discrimination power ranging from 59% for Bruce 43 to 87% for Bruce 22. Bruce 09, Bruce 11, Bruce 16, Bruce 42, and Bruce 43 were confirmed to remain stable <i>in vitro</i> among the 15 VNTR loci selected.<br/><b>Conclusion</b><br/> The results of this study suggest that the five loci subsets may be a useful epidemiological tool for investigating <i>B. abortus</i> biovar 1 outbreak.