Abstract: Objective To investigate the effect of miR-148a targeting DNMT1 on the proliferation and apoptosis of endometrial carcinoma. Methods The expression of miroRNA-148a (miR-148a) in normal and cancerous endometrial tissues was detected by quantitative real time polymerase chain reaction (qRT-PCR) and the correlation between miR-148a and clinical indicators was analyzed. Endometrial cancer cells HEC-1B were transfected with miR-148a mimics in vitro by Lipofectamine 2000. The transfection efficiency was detected by qRT-PCR and proliferative activity and apoptotic percentage of cells were measured by MTT and flow cytometry. Transwell and Western blot were used to detect the ability of cell migration and invasion. Target sites of DNMT1 and miR-148a were determined by online software Target Scan, and the targeting relationship between DNMT1 and mir-148a was verified by luciferase reporter gene. Results Compared with normal tissues,the expression of miR-148a in endometrial carcinoma tissues was significantly decreased. Overexpression of miR-148a inhibited the proliferation, suppressed cell migration and invasion ability, and promoted cell apoptosis of HEC-1B cells. DNMT1 is the target gene of miR-148a. miR-148a inhibited tumor growth and DNMT1 gene expression in mice. Conclusions miR-148a regulates DNMT1 to inhibit the cell proliferation, migration and invasion ability promotes the percentage of cell apoptosis.