Certain patients with stage IIIA-N2IIIB non-small cell lung cancer (NSCLC) have surgical opportunities after induction therapy. Two to four cycles of neoadjuvant chemoimmunotherapy (NCIT) are commonly used. However, whether the number of cycles of NCIT has an impact on the pathological response has not been extensively investigated. The intent of this study was to explore the impact of the number of NCIT cycles on the pathological response of patients with stage IIIA-N2IIIB NSCLC.This retrospective single-center study reviewed patients with stage IIIA-N2IIIB NSCLC without positive driver genes who received two to four cycles of NCIT followed by complete resection. The primary endpoint was the major pathological response (MPR) rate. Univariate and multivariate logistic regression analyses were performed to explore the risk factors for the MPR. The objective response rate (ORR) was also compared between different cycles of NCIT.Among the 170 patients included in our final analysis, the MPR rate was 58.24%, and the pathological complete response (pCR) rate was 37.06% in the overall cohort. The MPR rates were 58.97%, 62.50%, and 50.00% in the two-, three- and four-cycle NCIT groups, respectively. Multivariate regression analysis revealed that preoperative assessment of the radiographic response to NCIT, partial response/complete response (PR/CR), was the only independent prognostic factor for the MPR (p < 0.001).We confirmed that preoperative PR/CR was important in predicting the MPR, whereas the number of cycles of NCIT did not influence the MPR rate in patients with stage IIIA-N2IIIB NSCLC.© 2025. Society of Surgical Oncology.