Healthcare-Acquired Infection (HCAI) persisted as one of the most alarming problem in healthcare with its most common source comes from Klebsiella pneumoniae infection. Apple Cider Vinegar has been widely known as a traditional herbal medicine with studies on its antimicrobial properties that contained in its Acetic Acid, Polifenol, Flavonoid, and Fenolic Acid components. This study is conducted to determine the effect of Apple Cider Vinegar on the In Vitro Growth of Klebsiella pneumoniae Bacteria. Methods that will be used to provide the results are through Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) tests. The concentrations of Apple Cider Vinegar that will be used are 100%, 50%, 25%, 12.5%, 6.25%, and 3.125%. Chi-Square test is applied as the statistical analysis of this research. The study has shown a result of MIC and MBC concentrations as low as 3.125% of Apple Cider Vinegar with no bacterial growth observed. The results has been statistically significant by Chi-Square and Fisher Exacts tests with p<0.005. There is an effect of Apple Cider Vinegar on the In Vitro Growth of Klebsiella pneumoniae Bacteria
