Abstract: Objective To investigate the influence of sleep status in early pregnant women on the occurrence of gestational diabetes mellitus (GDM). Methods In this prospective study, 542 pregnant women in early pregnancy were selected as subjects. The sleep time, insomnia, pre-gestational body mass and basic information of the subjects were collected by the trained investigators through questionnaire. At the 24th to 28th pregnant week, the body mass of each subject was measured and oral glucose tolerance test (OGTT) was conducted. The diagnosis of GDM was followed the guidelines of diagnose and treatment of gestational diabetes mellitus in China (2014). A non-conditional logistic regression method was adopted to analyze the correlation between sleep status of early pregnant women and the occurrence of GDM. Results The numbers of subjects in sleep deficiency group, sleep sufficiency group and sleep excessive group were 16 (2.95%), 268 (49.45%) and 258 (47.60%), respectively. The incidences of GDM for sleep deficiency group, sleep sufficient group, and sleep excessive group were 62.50%(10/16), 25.75%(69/268) and 22.09% (57/258), respectively, the difference was statistically significant (χ2=11.280，P2=8.410, 11.218, P2=4.813，POR)=7.38, 95% confidence interval (CI): 2.25-24.17〕. However, the association between insomnia and the occurrence of GDM was not found. Conclusion Sleep deficiency in early pregnancy may be a risk factor for the occurrence of GDM.