The article focuses on the study of the positive emotion of humor in persons with intellectual disability. The subject is introduced a brief look at some of the main theories, definitions and models used in attempting to explain psychologically this human phenomenon; in order to link them to the general characteristics of intellectual disability, from an evolutionary perspective. Results from several studies on sense of humor are reviewed, where groups are compared, largely groups of children, with different characteristics such as autism, learning disability and intellectual disability. Next, more detailed attention is given to adult persons with intellectual disability, analyzing some of the conditioning factors that influence their appreciation of humor and their own humor-related behavior. Finally, several conclusions are drawn, including that sense of humor is a very important matter for the emotional well-being also of the intellectually disabled, and the need to expand our current knowledge of this topic.