Human Immunodeficiency Virus (HIV) prevalence among young gender-diverse (a wide range of gender identities for people whose gender identity is different from the sex that they were assigned at birth) individuals is high but testing coverage among this key population remains low. We aim to evaluate strategies for outreach, HIV testing, and linkage to proper management in young men-who-have-had-sex-with-men (MSM, homosexual male) and transgender women (TGW) in Bangkok, Thailand. The "YM2M outreach program" consisted of two strategies: 1) online platforms (OP) and 2) physical outreach activities (POA). Participant questionnaires were completed on a voluntary basis during outreach activities during 2018-2021. Demographic and behavioral characteristics were assessed for association with HIV positivity. A total of 3,972 homosexual male and TGW participated in the YM2M program: 2,973 by OP and 999 by POA. Of 2,230 participants who reported gender identity, 603/1,392 (43.3%) of OP and 252/985 (25.6%) of POA were gender diverse. Of 631 (21.2%) participants in OP and 970 (97.1%) in POA who underwent testing, 286 (45.3%) in OP and 41 (4.2%) in POA were HIV-positive. The venue reporting highest HIV yield was the Mor-Lam (11.5%). Among those with an HIV-positive test, 175 (61.2%) from OP and 23 (51.1%) from POA were successfully linked to HIV care. The independent factors associated with HIV positive in OP were being youth (adjusted odd ratio (aOR), 0.37; 95%CI 0.16-0.81; P = 0.01) and suspected or confirmed STI (aOR 15.39; 95%CI 7.17-33.03, P<0.01); while those in in POA at Mor-Lam were being gender diverse (aOR, 8.43; 95%CI 1.94-36.62; P<0.01) and reactive syphilis test (aOR, 5.40;95%CI 2.45-11.88; P<0.01). Linkage to pre-exposure prophylaxis (PrEP) among HIV-negative participants was low, 4.9% and 2.6% in OP and POA participants, respectively. While uptake of HIV testing was higher in POA while OP was more effective in identifying undiagnosed people living with HIV/AIDS and linking them to care. Neither strategy was considered effective in linkage to PrEP.