Prescribing gender-affirming hormonal therapy in transgender men (TM) not only induces desirable physical effects but also benefits mental health. In TM, testosterone therapy is aimed at achieving cisgender male serum testosterone to induce virilization. Testosterone therapy is safe on the short term and middle term if adequate endocrinological follow-up is provided. Transgender medicine is not a strong part of the medical curriculum, although a large number of transgender persons will search for some kind of gender-affirming care. Because hormonal therapy has beneficial effects, all endocrinologists or hormone-prescribing physicians should be able to provide gender-affirming hormonal care.