Goserelin is a drug used in prostate cancer, where drug-induced liver injury (DILI) rarely occurs. One patient had repeated increases in ALT/AST after each subcutaneous injection of goserelin, which improved after discontinuation of the drug and hepatoprotective treatment. When goserelin was re-administered, there was a repeated increase in ALT/AST, confirming positive re-stimulation. According to the EASL, the R-value was approximately 6.0, indicating a hepatocellular type of liver injury; Hy's law was not fulfilled. Causality was assessed by the updated RUCAM (2016) with a total score of 11, corresponding to a highly probable association with goserelin. The peak value of ALT did not exceed 5 times the upper limit of the norm. The case shows the importance of close biochemical monitoring, especially at higher doses or re-exposure. Liver biopsy was not performed.