摘要:Morningness–eveningness is the preference for different times of day for activity and sleep. Here, we addressed the effects of sleep behavior and morningness–eveningness on sociosexuality. Three hundred students (M age = 22.75 years, with 95% between 18 and 28) participated online, answering questions about morningness–eveningness (rMEQ [Reduced Morningness–Eveningness Questionnaire]), midpoint of sleep on free days (MSF), sleep duration, and the Sociosexuality Orientation Inventory–Revised (SOI-R). The SOI-R contains three subscales, Behavior, Attitude, and Desire. Evening orientation and short sleep duration were related to a higher total SOI-R and to the three subscales. Based on the linear models, the strongest effect on sociosexuality was produced by gender (27% explained variance) while age accounted for 6% of variance. Nonadditive variance explained by sleep–wake behavior was 7% (MSF), 4% (sleep duration), and 4% (rMEQ scores; 3% rMEQ-based typology). Older age was related to less-restricted sociosexuality, and men were less restricted than women in Attitude and Desire. Sleep duration and rMEQ scores were associated with Attitude and Desire; but only MSF was significantly related to Behavior. The data show that sleep–wake variables are associated with sociosexuality, with evening orientation and shorter sleep duration being related to a less-restricted sociosexuality.