Prostitution is an exchange of sex for money or other favors and the male prostitute is a biological man who practices prostitution. Researchers have been dividing them into Male Sex Workers (MSWs) with or without Gender Identity Disorders (GID). Typological studies that evaluate the differences between both groups can help researchers develop effective management proposals for this complex population, but this type of study is very scarce. MSWs represent a high risk population for sexually transmitted diseases (STD), showing a high prevalence of alcohol and drug use and unsafe sexual practices. Furthermore, they show some specific characteristics, such as low educational level, history of leaving home and dropping out of school, poor life support and history of violence. Illegal activities are common, even before prostitution begins and many MSWs have been arrested, mainly the street workers. There are few studies about MSWs and a structural understanding of them is required. In this text, we present a literature revision and the initial data of our study that has evaluated the use of licit and illicit drugs, depression symptoms, impulsiveness, dimensional personality aspects and criminal history among male prostitutes.