Background: One of the main features of cancer, especially lung cancer (LC), is abnormal cell division. Abnormal expression of kinesin family member C1 (KIFC1/HSET), which is involved in mitotic cell division and ensures equatorial alignment of chromosomes during division, is observed in both premalignant and malignant lesions. There are no studies in the literature addressing the role of KIFC1 in the diagnosis and follow-up of LC. In this study, we investigated the epigenetic role of KIFC1 in the diagnosis, stage, and prognosis of various histological subtypes diagnosed with LC. Material and Methods: The expression and methylation status of the KIFC1 gene were examined after DNA/RNA isolation in tumor, conjugate normal tissue, and blood samples from 39 patients diagnosed with LC and in blood samples from 39 healthy controls. Changes in KIFC1 gene expression were examined by the Quantitative Real Time-PCR (qRT-PCR) method after cDNA synthesis following RNA isolation. The Methylation-Specific PCR (MSP) method was used to determine the methylation status of the KIFC1 gene. In this study, the expression/methylation profiles of the KIFC1 gene and the clinical and pathological characteristics of the patients were analyzed by statistical methods. Result: Hypomethylation was detected in 95.8% of the 62.1% of patients’ tissues with increased KIFC1 gene expression. The expression level of the KIFC1 gene was found to be increased 3.2-fold in the tumor tissues of the patients compared with the conjugated normal tissues and 2.4-fold in the serum of the patients compared with the healthy serum. Statistical comparison of patients' clinical parameters and methylation and expression results revealed statistical significance between KIFC1 expression and metastasis, tumor stage and tumor grade. Conclusion: In conclusion, the increase in the expression level of the KIFC1 gene is higher in patients diagnosed with LC than in the healthy population, and therefore, the increase in the expression level of the KIFC1 gene due to hypomethylation can be used as a screening biomarker in LC. It can also be considered that the methylation profile of the KIFC1 gene may be a potential biomarker for determining the subtype of squamous cell carcinoma in LC. The results of the study need to be analyzed and continued with a larger number of patients.