The cause of squamous cell carcinoma is not clear at present, and it is mostly believed to be related to physical (e.g. light, radiation), chemical (e.g. aflatoxin, nitrite), biological (e.g. human papillomavirus, EBV), hereditary or gene mutation and other factors. Squamous cell carcinoma can occur in different parts of the body, such as skin, lung, esophagus, cervix, etc. Squamous cell carcinoma of the skin is often related to sunlight exposure, squamous cell carcinoma of the lung is often related to smoking and air pollution, squamous cell carcinoma of the esophagus is often related to eating foods that are too hot or high in nitrites, and cervical carcinoma is often related to human papillomavirus infections and sexual behavior disorders. In addition to the above factors, it may also be related to heredity, gene mutation and other factors. Although it has been found that squamous cell carcinoma may be related to the above factors, the underlying causes are not clear and still need medical exploration and discovery. Patients found with squamous cell carcinoma are advised to consult with hospitals in time and take active treatment under the guidance of doctors in order to obtain a better prognosis.