The authors assessed sexual functioning among treatment-seeking obese men (n = 91) and women (n = 134) using the comprehensive validated Sexual Functioning Questionnaire. Scores were lower for women than for men, indicating reduced sexual functioning. Men's scores fell between those of a group of cancer survivors and a general population group, whereas women generally had lower scores than both of these groups. Increasing body mass index was associated with decreasing sexual functioning only for arousal and behavior. Sexual functioning was also reduced on most subscales for individuals who reported sexual inactivity in the past month.