Positive views of adolescents' sexuality have only begun to garner interest in the last two decades. Despite great strides in this emerging area, progress is limited by the paucity of valid and reliable measures among this population. The goal of this study was to validate the widely used adult five-item Global Measure of Sexual Satisfaction (GMSEX) in a large sample of sexually active adolescents. A total of 1,036 adolescents (516 girls, 49.8%) aged between 14 and 17 years (Mage = 14.62; SD = 0.66) were recruited to investigate the reliability and validity of the GMSEX. The GMSEX yielded strong psychometric properties in adolescents, including factor structure, measurement invariance, and reliability. Results showed that the scale works similarly for boys and girls as well as for heterosexual, cisgender, and sexual minority adolescents. The GMSEX is a short, reliable, and valid measure of sexual satisfaction that can be used in future studies focusing on adolescents' sexuality and relationships.