Objective： To explore the correlation between progestogen supplementation in early pregnancy and incidence of gestational diabetes mellitus （GDM） . Methods： 663 cases of low-level progesterone pregnant women in early pregnancy were selected，424 cases were supplemented with progesterone as the observation group，239 cases were not supplemented with progesterone at the same time as the control group. Pregnant women in the observation group were divided into oral group and intramuscular group with low dose，medium dose and high dose according to different administration methods and doses. The incidence of GDM in each group was compared after treatment. Results： The incidence of GDM in the observation group was higher than that in the control group （P<0.05）； there was no significant difference in the incidence of GDM between the oral group and the control group （P>0.05）； the incidence of GDM in the intramuscular injection group was higher than that in the control group （P<0.05）； the incidence of GDM in the low，medium and high dose groups increased in turn （P<0.05） Conclusion： . Supplement of progesterone in early pregnancy is associated with the incidence of GDM. Oral administration has no significant effect on the incidence of GDM. Intramuscular administration increases the incidence of GDM in a dose-dependent manner.