A retrospective, cross-sectional study was conducted to describe the occurrence of daytime sleep (DS) and to examine factors associated with DS in nursing home residents. We used the Minimum Data Set 2.0 records of 300 residents in a nursing home from January 2005 to March 2010. Descriptive statistics, independent t-test, chi-square, Pearson correlations, and logistic regression were utilized in analysis. About 71.3% of the residents slept more than 2 hours during the day, and this was significantly associated with residents’ comorbidity (t = 2.0, p = .04), cognitive performance (t = 7.3, p = .01), activities of daily living (t = 3.7, p = .01), and social involvement (t = –7.6, p = .01). Cognitive performance and social involvement significantly predicted the occurrence of DS with social involvement being the strongest predictor (odds ratio: .58; 95% confidence interval: [.45, .75]). The findings suggest that interventions to engage nursing home residents in more social activities during the day may be beneficial to minimize their DS, especially for those who have difficulties with engaging socially on their own.