Performing the right antibacterial testing definitely has become one of the most critical aspects in evaluating the antimicrobial abilities of the textile materials. However, antimicrobial testing is by nature complex, delicate, and laborious. Therefore most of antimicrobial analysis methods, either antibacterial or antifungal, rely on subjective assessments. In this study, an image analysis method has been developed to count the colonies during the process of antibacterial test for textile materials. The reliability of the the software was investigated by comparing the result of image analysis with that of manual counting, which showed that the reliability of the newly proposed method was sufficiently high.