Background In recent years, immune checkpoint inhibitors (ICIs) have been introduced as a first-line treatment for patients with non-small cell lung cancer (NSCLC), which are expected to achieve long-term survival. However, despite ICI treatment, many patients do not achieve sustained effects from immunotherapy. To date, detailed studies on the long-term survival in patients with NSCLC without driver gene mutations remain limited. Methods We conducted a retrospective analysis of 97 patients with NSCLC treated with ICIs. Patients with a more than 3-year survival following treatment were classified into the long-term survival group, and those who did not were classified into the non-long-term survival group. The clinical information was compared between the two groups. Results Of the 97 patients, 22 (22.7%) were classified into the long-term survival group. The long-term survival group had a significantly higher proportion of younger patients, patients who responded to initial ICI treatment, and patients who discontinued treatment due to immune-related adverse events (irAEs). Multivariate analysis identified ”switching administration,” adenocarcinoma, and low neutrophil-to-lymphocyte ratio (NLR) as significant independent factors predicting long-term survival. Conclusion Initial treatment response and the appropriate discontinuation of ICI therapy in the event of irAEs may contribute to the long-term survival of patients with NSCLC. Furthermore, when considering the continuation of ICI therapy, the introduction of “switching administration” may also be beneficial.