HIV activism has a long history of advancing HIV treatment and is critical in dismantling HIV-related stigma. This study evaluated the psychometric quality of the HIV Activist Identity, Commitment, and Orientation Scale (HAICOS) to assess clinicians' propensity towards HIV activism in Malaysia. From November 2022 to March 2023, 74 general practitioners and primary care physicians in Malaysia participated in the study. The exploratory factor analysis (EFA) extracted an internally consistent three-factor solution with 13 items: (1) HIV activist identity and commitment, orientation towards (2) day-to-day, and (3) structural activism. The Cronbach's alpha value was 0.91, and intra-class correlation coefficient for test-retest reliability was 0.86. Stigma-related (prejudice and discrimination intent) and clinical practice (comfort in performing clinical tasks with key populations and knowledge about HIV pre-exposure prophylaxis) measures supported the construct validity of the scale. The study provided concise, structurally valid, and reliable measures to evaluate HIV activism among clinicians.