Objective: To examine sleep characteristics of preschool children who were born preterm, which could provide a reference for the future intervention in the risk population. Methods: This retrospective cohort study was conducted from March 2017 to November 2018 in hospitals in cities of Guangzhou, Zhongshan, and Shenzhen, Guangdong Province, China, we recruited 202 preschool children aged 4-6 years, including 40 early-and moderate preterm (gestational age <34 weeks), 56 late preterm (34-36 weeks) , and 106 full-term preschool children (≥37 weeks). Caregivers reported children’s sleep time and habits using Chinese version of Children’s Sleep Habits Questionnaire (CSHQ). Results: Compared to the full-term group, the very-or-moderate-preterm group had shorter nighttime sleep duration (9.07±0.75 vs 9.33±0.59 h; adjusted β=-0.33), shorter total sleep duration (10.39±0.86 vs 11.05±1.32 h; adjusted β=-0.70), higher sleep duration score of CSHQ (4.60 ± 1.57 vs 3.97 ± 1.25 points; adjusted β=0.58), and higher sleepdisordered breathing score of CHSQ (3.78±1.27 vs 3.41±0.71 points; adjusted β=0.49). The late preterm group had lower parasomnias score of CSHQ (8.40±1.65 vs 8.75±1.72 points; adjusted β=-0.57), than the full-term group(P<0.05). When gestational age was analyzed as a continuous variable, it was positively associated with the total sleep duration (adjusted β= 0.06), while was inversely associated with sleep-disordered breathing scores of CSHQ (adjusted β=-0.06). Conclusion Very-or-moderate preterm children have shorter sleep duration and more sleep disordered breathing problems than full-term children, and have more disorders of sleeping duration and sleeping breathing than full-term children, while the late preterm children have less sleeping disorders than full-term children. The children of lower gestational age can have shorter sleep duration and more sleep-disordered breathing which should be addressed in future intervention.