As consumption of kimchi has increased, factories have begun to produce this traditional Korean fermented vegetable dish on a large scale. Following the rise in manufacturing, the hygienic conditions under which commercial kimchi is being made have become an issue. We isolated 17 coliform bacteria from commercial kimchi that had not been fully fermented. These bacteria were partially identified as one of seven different species from three genera by 16S rDNA sequence analysis as follows: Enterobacter intermedius, Ent. cloacae, Ent. amnigenus, Klebsiella terrigena, K. ornithinolytica, K. oxytoca, and Hafnia alvei. Lactobacillus paraplantarum KNUC25 has been isolated from over-fermented Chinese cabbage kimchi and its antimicrobial activity reported in the literature. In our study, the KNUC25 strain showed antibacterial activity against isolated coliform bacteria and some pathogenic coliform bacteria through spot-on-the-lawn tests and viable cell tests. Through development and use of a cell-free supernatant of L. paraplantarum KNUC25, we effectively controlled coliform bacteria in commercial kimchi.