Here, we report a case of abiraterone acetate withdrawal syndrome with transient prostate-specific antigen decrease after progression to castration-resistant disease while using upfront abiraterone therapy for high-risk prostate cancer.<h4>Case presentation</h4>A 73-year-old man with hormone-sensitive high-risk prostate cancer with multiple bone metastases (prostate-specific antigen level, 294.109 ng/mL) received upfront abiraterone/prednisolone combination and androgen deprivation therapy. The gene discussed is KLK3; the disease is prostate cancer.