OBJECTIVE To investigate the oral health literacy (OHL) of nurses and explore the factors affecting their OHL. BACKGROUND OHL is important for improving the oral health outcomes. Nurses' OHL may affect the oral health of themselves, families, and patients. Few studies have examined the OHL and its related factors among nurses. METHODS A cross-sectional design following the STROBE guideline. METHODS A total of 449 nurses were recruited from tertiary hospitals in the minority areas of southwest China. The participants completed an online questionnaire, which contained questions related to the OHL, sociodemographic factors, general health, oral health and related behaviours, oral health knowledge, attitudes, and oral health-related quality of life. OHL was measured using the validated Chinese version of the short-form Health Literacy of Dentistry (HeLD-14) scale. Descriptive statistics, the Mann-Whitney U test, Spearman's correlation, and multiple linear regression analysis were used to analyse the data. RESULTS The median HeLD-14 score (p25-p75) was 50.0 (44.0-54.0). The regression model for OHL was found to be significant. The factors that influenced OHL included oral health knowledge, oral health attitudes, self-reported oral health, annual household income, and dental flossing; these factors accounted for 13.9% of the variance in OHL. CONCLUSIONS The nurse' OHL has room for improvement. Nurses' OHL could be improved by enriching their oral health knowledge, promoting their positive oral health attitudes, increasing their household income, and helping them build correct oral health behaviours. CONCLUSIONS The findings of the study could be used to make a case for changing nursing curricula. Oral health knowledge curriculum or programmes targeted towards nurses should be developed to improve their OHL. No Patient or Public Contribution.