Oral cancer is the fifth most common type of malignant neoplasm worldwide. The best-known risk factors for the development of this lesion are tobacco, alcoholism, papillomavirus infections and, more recently, the use of pesticides, substances considered carcinogenic to human health. In the study presented in this book, we evaluated the occurrence of 132 cases of squamous cell carcinoma of the mouth in a public laboratory in the state of Mato Grosso using georeferencing from 2005 to 2011, profiling the cases according to gender, age and year of diagnosis. The cases evaluated came from 49 municipalities, with the most significant originating in Cuiabá, Várzea Grande and Rondonópolis. It was possible to conclude that the data evaluated did not allow us to find a cause and effect relationship between squamous cell carcinoma of the mouth and pesticide use.