Objective: To analyze the association between the division of domestic housework and generalized anxiety disorder (GAD) during the COVID-19 pandemic in mothers of preschool children. Materials and methods: This cohort study included mothers who had children in 2019 in the municipality of Rio Grande, southern Brazil. These women were followed up in 2020. The presence of GAD was assessed using the Generalized Anxiety Disorder 7-item (GAD-7) scale, and the division of domestic housework was evaluated with the "Division of Labor by Gender" instrument. Descriptive and bivariate analyses were conducted. Bivariate associations were tested using Pearson's chi-square (x2), while multivariate analyses were performed using Poisson regression to calculate prevalence ratios (PR) with 95% confidence intervals (95% CI). Results: A total of 908 mothers from the 2019 Rio Grande Birth Cohort participated ...