Purpose: This study was performed to identify the risk factors for oral mucosa pressure ulcer development in intubated patients in adult intensive care unit. Methods: Comparative descriptive study design using prospective observational design and medical record review was used. The inclusion criteria of case was that a) patients of 18 years in their age, b) patients with endotracheal tube. Data of 34 patients were analysed. Descriptive statistics, chi-square test, Fisher’s exact test, Mann-whitney test, Spearman’s rho correlation coefficients, and multiple logistic regression analysis were used. Resampling methods such as bootstrap was used in this study because of small number of patients. Results: Oral mucosa pressure ulcer developed in 44.1% of the intubated patients. The risk factors of oral mucosa pressure ulcer were steroid use, biteblock use and serum albumin level. Compared to the non-user of steroid, user of steroid had 32.59 times (95% CI: 1.47-722.44) higher risk of developing oral mucosa pressure ulcer. The user of biteblock had 18.78 times (95% CI: 1.00-354.40) and albumin level had 0.03 times (95% CI: 0.00-0.80) higher risk of oral mucosa pressure ulcer incidence. Conclusion: Based on the results of this study, tailored pressure relief strategies considering sex and therapeutic condition should be provided to decrease oral mucosa pressure ulcer.