Objective：To explore the expression of transcription factor EB（TFEB） in the mouse endometrium during the peri-implan－tation period，and to preliminarily investigate the role of TFEB in endometrial decidualization in early pregnant mice. Methods：A normal pregnant mouse model was established，and the mouse endometrium on the 4th（D4），5th（D5），and 6th（D6） days of early pregnancy and the endometrial implantation site tissue（IS） and the inter-implantation site tissue（IIS） on D5 were collected；a pseu－dopregnant mouse model was established and the mouse endometrium on the 4th（PD4），5th（PD5），and 6th（PD6） days of pseudo－pregnancy was collected. An in vivo artificial decidualization model was established and mouse endometrial tissues of the control side and induced side of mice were collected. An in vitro artificial decidualization model was established，and the mouse endometrial stromal cells of the control group and the induced group were collected. Western blot and real-time PCR were used to measure the mRNA and protein expression of TFEB in the mouse endometrium and in mouse endometrial stromal cells. The distribution and expression of TFEB in the mouse endometrium of D5 were measured by immunohistochemistry. Results：The expression of TFEB on D4，D5，and D6 gradually decreased with increasing days of pregnancy. The mRNA and protein expression of TFEB in the endometrial IS on D5 was significantly lower than that in the IIS on D5. The mRNA and protein expression of TFEB in the endometrial tissue of the induced side was significantly lower than that in the endometrial tissue of the control side. The mRNA and protein expression of TFEB in endometrial stromal cells was significantly lower in the induced group than in the control group. Conclusion：TFEB may be involved in the endometrial decidualization in early pregnant mice，but its specific regulatory role needs to be further explored.