Gastric-type endocervical adenocarcinoma (GEA) usually exhibits notable aggressiveness and resistance to current therapies. A high expression of programmed death-ligand 1 (PD-L1) was previous reported in GEA and indicated it might benefit from immunotherapy targeting programmed cell death protein 1 (PD-1)/PD-L1. In the present study, the efficacy of immunotherapy in a panel of patients with GEA was explored, aiming to provide the first-hand evidence on this topic. A total of 44 pathologically diagnosed patients with GEA were recruited from the First Affiliated Hospital of Zhengzhou University and the Cancer Hospital of Zhengzhou University. The clinical and pathological information including age, tumor stage, treatments and prognosis were retrieved from our medical records system. Kaplan-Meier analysis was conducted to evaluate the role of immunotherapy on patients' overall survival (OS) and progression-free survival (PFS). According to the treatments, patients with GEA were divided into two groups: The immunotherapy group (n=19) and the non-immunotherapy group (n=25, the control group). In the immunotherapy group, 9 patients received PD-1/PD-L1 inhibitors as part of their primary treatment, while the remaining 10 received it after tumor recurrence/metastasis. Compared with the control group, the use of immunotherapy during primary treatment significantly extended PFS (median PFS: 14 vs. 6 months, P=0.004) and OS (median OS: 24 vs. 16 months, P=0.019). However, in the 10 patients who initiated immunotherapy after tumor recurrence/metastasis, the survival benefits were only observed for OS (median OS: 33.5 vs. 16 months, P=0.013) but not PFS. Furthermore, the efficacy of immunotherapy was more significant in patients with PD-L1-positive GEA than those PD-L1-negative cases, which improved both the PFS (median PFS: 17 vs. 7 months, P=0.002) and OS (median OS: 36 vs. 16 months, P<0.001). This is the first study, to the best of our knowledge, reporting the efficacy of immunotherapy for GEA. It was demonstrated that the earlier use of PD-1/PD-L1 inhibitors was significantly associated with an improved prognosis, and PD-L1 status could predict the response of immunotherapy. These preliminary findings warrant further validations in the future.