Objective: We estimated the relationship between dietary behaviors and sleep quality in adults. Methods: Using data from the 2015 Ningbo Adult Chronic Diseases and Risk Factors Survey, a total of 5160 participants were included in this study. Sleep quality was measured by the Pittsburgh Sleep Quality Index (PSQI). PSQI score ≥ 7 was defined as poor sleep quality. Logistic regression was used to estimate the associations between dietary behaviors and sleep quality. Linear regression was used to explore the associations between dietary behaviors and PSQI total score. Results: Approximately 8.6% (n = 442) participants reported poor sleep quality. After adjusted for multivariates, there was 0.022 point increase in PSQI score for every gram increase in each meal consumption of soy sauce (β = 0.022, p = 0.001). Less intake of dark fruits, water and more intake of alcohol were associated with higher PSQI score (β = −0.394, p = 0.001; β = −0.246, p = 0.001; and β = 0.217, p = 0.005, respectively). Conclusions: About 8.6% (n = 442) adults reported poor sleep quality in Ningbo. Intake of soy sauce and alcohol were positively associated with poor sleep quality, and consumption of dark fruits and water were positively associated with good sleep quality.