To develop an evidence-based guideline for the diagnosis and treatment of antipsychotic-induced hyperprolactinemia by adapting existing high-quality clinical guidelines with a view to improve the clinical symptoms and long-term quality of life of patients by providing appropriate management. This guideline was developed according to the ADAPTE methodology. The adaptation process included determining key health questions, systematically searching and screening guidelines, evaluating the quality and contents of these guidelines, deriving recommendations for key questions, and performing a peer review. The selection criteria for the guideline search were (1) evidence-based guidelines, (2) published within the last 5 years, and (3) written in English or Korean. After evaluating the quality and content, we finally selected three guidelines for adaptation. The final output of the development process was 25 recommendations for 10 key questions. We adopted the Agency for Health Research Quality methodology and presented the level of evidence from levels I to IV. In addition, we defined the recommendation grades from grade A (strongly recommended) to D (no recommendation) based on the level of evidence and clinical significance of the recommendation. The development and dissemination of the adapted guideline is expected to increase the certainty of medical decision making and improve the quality of medical care. Further studies on the effectiveness and applicability of the developed guideline are necessary.