Objective To analyze the value of serum microRNAs (miR-218, miR-329, and miR-567) in predicting the clinical efficacy of programmed death-1 (PD-1) inhibitor combined with synchronous chemotherapy in patients with non-small cell lung cancer (NSCLC). Methods A total of 160 patients with NSCLC treated with PD-1 inhibitor combined with synchronous chemotherapy in Taiyuan Hospital, Peking University First Hospital between January 2021 and January 2023 were prospectively selected as the study objects by convenience sampling, and the serum levels of miR-218, miR-329, and miR-567 and the clinical efficacy of the patients were collected. According to the clinical efficacy, the patients were divided into remission group (partial remission and complete remission) and non-remission group (stable disease and disease progression). Receiver operating characteristic (ROC) curve was used to analyze the predictive value of serum miR-218, miR-329 and miR-567 levels in the clinical efficacy of PD-1 inhibitor combined with synchronous chemotherapy in patients with NSCLC. Results Of the 160 patients, 34 (21.2%) had disease progression, 85 (53.1%) had stable disease, 39 (24.4%) had partial remission, and 2 (1.2%) had complete remission. They were divided into remission group (41 cases) and non-remission group (119 cases). Multiple logistic regression analysis showed that high levels of serum miR-218, miR-329, and miR-567 could promote the clinical efficacy of PD-1 inhibitor combined with synchronous chemotherapy in patients with NSCLC (all P<0.05). ROC curve analysis showed that, for predicting the clinical efficacy of PD-1 inhibitor combined with synchronous chemotherapy in patients with NSCLC according to the cut-off value of the joint prediction probability of serum miR-218, miR-329, and miR-567, the area under the ROC curve was 0.938 [95% confidence interval (0.855, 0.964)], and the sensitivity, specificity, positive predictive value, and negative predictive value were 82.9%, 92.4%, 79.1%, and 94.0%, respectively. Conclusion The combined detection of serum miR-218, miR-329 and miR-567 levels has a high predictive value for the therapeutic effect of PD-1 inhibitor combined with synchronous chemotherapy in patients with NSCLC.