Background: Wound closure in pressure ulcers has a low rate of success. A tool is required to establish the right moment for wound closure. Matrix metalloproteinase-9 (MMP-9) is the main protease responsible for matrix degradation in chronic wounds. Its activity is regulated by Tissue Inhibitors of Metalloproteinase-1 (TIMP-1). The MMP-9/TIMP-1 ratio is inversely proportional to the success of wound healing in pressure ulcers. The type and number of certain bacteria also determine the success of wound closure. This study aims to explore the relationship between the bacterial load as well as the TIMP-1/MMP-9 ratio to determine wound closure success in pressure ulcers. Methods: A hospital-based nested case-control was conducted in 24 pressure ulcer patients who underwent wound closure and were evaluated for 3 weeks. The relationship between variables was analyzed with bivariate analysis, while its strength was assessed by the contingency coefficient. We also performed a multivariate analysis with logistic regression to see which variables are more dominant in determining wound closure success. Results: TIMP-1/MMP-9 ratio, as well as the bacterial load, was significantly associated with successful wound closure. The cut-off point of TIMP-1/MMP-9 ratio in the successful group is 0.72 ? 0.31 (P-value = 0.032). TIMP-1/MMP-9 ratio > 0.732 is related to the success of wound closure. Type and number of bacteria are significantly different between the successful and unsuccessful group (P-value = 0.034). Conclusion: TIMP-1/MMP-9 ratio is more dominant than the bacterial load in determining the success of wound closure of pressure ulcers, with OR 11.45 vs. OR 0.63 compared to type and number of bacteria (P-value = 0.024).