The causes of squamous cell carcinoma have not yet been fully understood, but there are several reasons for the current research: 1, genetic factors, almost all malignant tumors are related to genetic background, the evidence is that if there is a patient with squamous cell carcinoma in the immediate family, his chance of developing squamous carcinoma is significantly higher than that of people who do not have relatives with squamous carcinoma, and scientists have also found genes related to the occurrence of squamous carcinoma, which are being studied in depth. 2. Viral infections can change the gene function of human body and cause squamous epithelial cells to become cancerous after virus infection. The most obvious example is cervical squamous cell carcinoma, the occurrence of which is closely related to human papillomavirus infection, and the chance of cervical cancer in people infected with this virus is significantly higher than that in those without infection. 3. chronic inflammation, it is a consensus among oncologists that chronic inflammation can lead to cancer occurrence. Chronic inflammation can also cause cancer in squamous epithelial cells by changing the function of normal cell genes. 4.Other factors, physical and chemical factors including chemical drugs and ionizing radiation can cause squamous cancer.