Sebaceous adenocarcinoma (SAC) mostly occurs in the elderly, and SAC in young and middle-aged population is inadequately investigated.To explore the clinical features and prognosis of young and middle-aged adults with SAC.Patients with skin SAC between ages 18 and 59 years from the Surveillance, Epidemiology, and End Results database (1975-2016) were eligible for this study.Seven hundred thirty-nine cases were identified. The proportion of extraocular SAC in the nonelderly increased from 1975-2005 to 2006-2016 ( p = .001), male predominance was observed in overall patients whereas female predominance in Asian population, and young patients had more head and neck SAC than middle-aged patients ( p = .014). The prognosis of young patients was better than middle-aged patients ( p = .004). Other independent prognostic factors included sex, marital status, tumor size, surgery, chemotherapy, and multiple primary cancer history.An increasing proportion of extraocular SAC was observed in young and middle-aged patients, and the young developed more head and neck SAC than the middle-aged. Female predominance was found in Asian population, and female patients had better prognosis. Younger age and married status indicated better prognosis, and around 20% of young and middle-aged patients might have poorer survival because of Muir-Torre syndrome.Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Society for Dermatologic Surgery, Inc.