AbstractObjectivesUrinary tract infection, urinary frequency, urgency, urodynia and haemorrhage are common post‐operative complications of thulium laser resection of the prostate (TmLRP). Our study mainly focuses on the role of finasteride in prostate wound healing through AR signalling.Materials and methodsTmLRP beagles were randomly distributed into different treatment groups. Serum and intra‐prostatic testosterone and DHT level were determined. Histological analysis was conducted to study the re‐epithelialization and inflammatory response of the prostatic urethra in each group. We investigated the role of androgen in proliferation and inflammatory response in prostate. In addition, the effects of TNF‐α on prostate epithelium and stromal cells were also investigated.ResultsTestosterone and DHT level increased in testosterone group and DHT decreased in finasteride group. Accelerated wound healing of prostatic urethra was observed in the finasteride group. DHT suppressed proliferation of prostate epithelium and enhanced inflammatory response in prostate. We confirmed that DHT enhanced macrophages TNF‐α secretion through AR signalling. TNF‐α suppressed proliferation of prostate epithelial cells and retarded cell migration. TNF‐α also played a pivotal role in suppressing fibroblasts activation and contraction.ConclusionTestosterone treatment repressed re‐epithelialization and wound healing of prostatic urethra. Finasteride treatment may be an effective way to promote prostate re‐epithelialization.