Platinum-based chemotherapy is the primary treatment option for advanced non-small cell lung cancer (NSCLC) patients without a driver gene mutation, but its efficacy is still modest. Through a potential synergistic effect, autologous cellular immunotherapy (CIT) composed of cytokine-induced killer (CIK), natural killer (NK), and T cells might enhance it. NK cells exhibited in vitro cytotoxicity toward lung cancer cells (A549 cells) following platinum therapy. Using flow cytometry, the expression of MICA, MICB, DR4, DR5, CD112, and CD155 on lung cancer cells was assessed. In this retrospective cohort study, there were included 102 previously untreated stage IIIB/IV NSCLC patients ineligible for tyrosine kinase inhibitor (TKI) target therapy who received either chemotherapy alone (n=75) or combination therapy (n=27). The cytotoxicity of NK cells for A549 cells was increased obviously and a time-dependent enhancement of this effect was also observed. After platinum therapy, the levels of MICA, MICB, DR4, DR5, CD112, and CD155 on the surface of A549 cells were increased. In the combination group, the median PFS was 8.3 months, compared to 5.5 months in the control group (p=0.042); the median overall survival was 18.00 months, compared to 13.67 months in the combined group (p=0.003). The combination group had no obvious immune-related adverse effects. The combination of NK cells with platinum showed synergistic anticancer effects. Combining the two strategies increased survival with minor adverse effects. Incorporating CIT into conventional chemotherapy regimens may improve NSCLC treatment. However, additional evidence will require multicenter randomized controlled trials.