Although healthcare waste management (HCWM) legislations prevail in Association of Southeast Asian Nations (ASEAN), there appears a prominent gap in standalone pharmaceutical waste management (PWM) legislation making harmonization of PWM challenging in the region. This review is aimed to comprehensively overview the PWM-related legislations in ASEAN, comprising of 10 economically rising countries in Southeast Asia. The relevant regulatory documents, that were promulgated till August 31, 2024 and that were in English or officially translated in English, were extracted from PubMed/Medline, Scopus, Science Direct, Google Scholar, and respective country's government websites. The documents were considered suitable based on their relevance, accessibility, and timeliness. The policy analysis revealed that all Member States in ASEAN lack specific legislations on PWM, and are managing pharmaceutical waste (PW) within the umbrella legislation of HCWM or biomedical waste management. The review discussed implications of joint ASEAN legislations, relevant guiding principles of waste management, and international guidelines relevant to PWM such as Basel Convention, Stockholm Convention, and the status of their endorsement in ASEAN. Some ASEAN countries such as Indonesia, Malaysia, Philippines, Singapore, Thailand and Vietnam have established infrastructures and regulatory setup for HCWM but still lack specific PWM legislations. ASEAN can foster harmonized legislative frameworks, facilities and technologies in PWM, raising public awareness and active participation to mitigate PW problem. The hard laws such as Acts, regulations, and ordinances are definitely aimed for PWM in ASEAN, but at least harmonized soft laws in the form of guidelines are imperative to harmonize PWM practice.