Background: PD-L1 is the main ligand is expressed on many tumors including lung cancer and is expressed in hematopoietic cells and various leukemia. The aim of this study was to evaluate the expression of PD-1 gene and the evaluation of cancerous grades of NSCLC and its subclasses from lung cancer patients in Tehran hospitals using Real-Time PCR. Materials and Methods: A total of 35 clinical samples were collected from patients with NSCLC-derived lung cancer from three hospitals in Tehran (Khatam Hospital, Athiyah Hospital, and Masih Hospital). Of the 35 samples collected in 2017, 20% of the patients were women and 80% of them were male. The range of patients’ age spectrum was 37 - 80 years. The disease grade of the patients in this study was varied and 22 different grades among them. To investigate the PDCD-1 gene expression level, after extraction of RNA and cDNA synthesis the Real-Time PCR was done and the expression of the gene was investigated. Results: The highest grade was IIIa which contained 6 patients (17.1%). 74% of adenocarcinoma cases were in T-categories of lung cancer and 25% of patients were in grade IIIa. Patients with the grade of T3 were observed in 4 samples, 2 had adenocarcinoma and 2 with SCC with age range of 55 -62 years. The results showed that the expression of PDCD-1 increased 2.46 Fold more in patients with lung cancer than NSCLC. Conclusion: The results of this study showed that there is a significant relationship between the PDCD1 or PD-1 expression of NSCLC-type lung cancer compared with healthy individuals, and using the RT-PCR for ease and rapidity it can be proved.