Background and Objective Children’s sleep habits are important for their health and development. Here, we investigated the relationship between sleep habits, behavior, personality, and social responsiveness in children. Methods A total of 38 preschool children were assessed using the Korean Child Behavior Checklist (K-CBCL), Junior Temperament and Character Inventory (JTCI), Children’s Sleep Habit Questionnaire (CSHQ), and Social Responsiveness Scale (SRS). Results Harm avoidance according to JTCI was positively correlated with bedtime resistance (r = 0.34; p = 0.04) and sleep anxiety on the CSHQ (r = 0.43; p < 0.01). Emotional lability on the K-CBCL was significantly associated with parasomnias (r = 0.38; p = 0.02), while lower social cognition and social communication scores on the SRS were associated with sleep anxiety (r = −0.34; p = 0.03) and parasomnias (r = −0.38; p = 0.01). Path analysis showed that among the JTCI subscales, both harm avoidance and persistence were significantly associated with social cognition. Conclusions Clinicians should pay particular attention to psychological components as potential contributors to sleep habits when managing sleep problems in preschool children.