Objective: To explore the value of programmed cell death protein 1 (PD-1), programmed cell death ligand 1 (PD-L1) and protein 53 (P53) in estimating the prognosis of patients with non-small cell lung cancer (NSCLC) after postoperative adjuvant chemoradiotherapy., Methods: The clinical data of 100 patients with NSCLC who were treated with adjuvant chemoradiotherapy after pulmonary lobectomy in our hospital were retrospectively analyzed. The expression levels of PD-1, PD-L1 and P53 in tumor tissues were detected by immumohistochemical staining. The efficacy of chemoradiotherapy and survival time between patients with positive and negative expression of PD-1, PD-L1 and P53 were compared respectively to evaluate the correlation of PD-1, PD-L1 and P53 with chemoradiotherapy results in NSCLC. General data of patients were analyzed by single factor analysis. Multivariate logistic regression analysis was used to identify independent risk factors impacting the prognosis of NSCLC patients with postoperative adjuvant chemoradiotherapy., Results: A significantly lower chemoradiotherapy effective rate and a remarkably shorter survival time were found in NSCLC patients with positive expression levels of PD-1, PD-L1 and P53 in tumor tissues as compared with those of negative results (all P<0.05). Single factor analysis revealed that gender, age, history of smoking, histological type, degree of differentiation, T stage, lymph node metastasis, expression levels of PD-1, PD-L1 and P53 showed significant correlations with the prognosis of NSCLC patients with postoperative adjuvant chemoradiotherapy (all P<0.05). High T stage (odds ratio (OR)=7.269), history of smoking (OR=5.128), lymph node metastasis (OR=4.647), PD-1 (+) (OR=7.556), PD-L1 (+) (OR=6.674), P53 (+) (OR=9.070), PD-1 (+) PD-L1 (+) (OR=6.095), PD-1 (+) P53 (+) (OR=6.752), PD-L1 (+) P53 (+) (OR=7.363), and PD-1 (+) PD-L1 (+) P53 (+) (OR=8.524) were determined by multiple logistic regression analysis to be independent risk factors influencing the effect of postoperative adjuvant chemoradiotherapy in NSCLC patients., Conclusion: There are numerous risk factors affecting the effect of postoperative adjuvant chemoradiotherapy in NSCLC patients, of which NSCLC patients with positive expression of PD-1, PD-L1 and P53 had a worse prognosis than those with negative results. PD-1, PD-L1 and P53 can serve as effective prognostic indicators for NSCLC after chemoradiotherapy. In clinical practice, monitoring these three indicators contributes to the adjustment of therapeutic regimen and gives some guidance., Competing Interests: None., (AJTR Copyright © 2022.)