Purpose The efficacy of programmed cell death protein 1(PD-1)/Programmed cell death 1 ligand 1 (PD-L1) inhibitors for endometrial cancer remain controversial, and guidelines are inconsistent on which are preferred therapies for advanced disease, or who develop metastases and recurrence. Therefore, we aimed to estimate the efficacy and safety of PD-1/PD-L1 inhibitors in endometrial cancer on a more complete database by adding multiple randomized trials. Methods A systematic and comprehensive search was carried out in PD-1/PD-L1 inhibitors monotherapy. Results The ORR of PD-1/PDL-1 inhibitors was 29%, and subgroup analysis showed that the pooled ORR of the proficient mismatch repair (pMMR) group was 4% and which was 45% of the deficient mismatch repair (dMMR) group. The DCR of PD-1/PD-L1 inhibitors was 48%, through subgroup analysis, we found that the DCR of the pMMR group was 21% and which was 58% of the dMMR group. The proportion of patients occurring overall adverse events was 65% and grade three or higher adverse events was 14%. The proficient mismatch repair (pMMR) group and the deficient mismatch repair (dMMR) group showed different results. Conclusion PD-1/PD-L1 inhibitors had shown little success in the pMMR population and better efficacy in the dMMR population.