Objective?To observe the effect of programmed cell death protein-1 (PD-1) inhibitor combined with anti-angiogenic drugs in the treatment of advanced lung adenocarcinoma, and to provide reference for clinical practice. Methods?60?patients with advanced lung adenocarcinoma admitted to the Boxing People’s Hospital from June 2020?to January 2022?were selected as the study subjects. They were divided into intervention group and control group according to the method of random number table, with 30?patients in each group. Patients in the intervention group were treated with PD-1?inhibitor combined with anti-angiogenic drugs, while patients in the control group were treated with anti-angiogenic drugs alone. Disease control rate, remission rate, biochemical index level, alpha-fetoprotein level and adverse reactions were compared between the two groups. Results?There was no significant difference in disease control rate between the two groups (P>0.05). The objective remission rate in the intervention group was higher than that in the control group (P<0.05). The levels of cytokeratin 19?fragment and carcinoembryonic antigen in the two groups after treatment were lower than those before treatment, and the intervention group was lower than the control group (P<0.05). The incidence of capillary hyperplasia in the intervention group was higher than that in the control group (P<0.05). There was no significant difference in the incidence of other adverse reactions between the two groups (P>0.05). Conclusion?In the administration of anti-angiogenic drugs, the addition of PD-1?inhibitor in the treatment of patients with advanced lung adenocarcinoma has a significant effect. It can effectively alleviate the disease and promote the patients to obtain a longer survival period. During clinical treatment, attention should be paid to the specific capillary hyperplasia of PD-1?inhibitor.