Objective:To monitor serum inflammatory cytokines during induction of benign prostate hyperplasia in dogs. Methods: This research was designed as a case-control study. There were 20 adult mixed-breed intact male dogs, which were divided into the normal group (n=10) and the benign prostate hyperplasia group (n=10). In the benign prostate hyperplasia group, benign prostate hyperplasia was induced by injection of testosterone (75.00 mg/dog, i.m.) and estrogen (0.75 mg/dog,i.m.) on day 0 (day of the first injection), day 21, day 42, and day 63. The doses of testosterone were doubled on days 21, 42, and 63. The normal group did not receive any injection. Blood sampling was performed from the jugular vein at days 0, 21, 42, and 63. The concentrations of interleukin-8, interleukin-10, and tumor necrosis factor-α (TNF-α)were assayed by enzyme-linked immunosorbent assay. Results:The levels of interleukin-8, interleukin-10 and TNF-αwere not significantly different between the normal group and the benign prostate hyperplasia group. Also, concentrations of the pro-inflammatory cutokines were not significantly different between the normal group and the BPH group in each day of sampling. Conclusions:In spite of the induction of benign prostate hyperplasia, changes in the concentration of blood serum inflammatory cytokines were not significantly different with that of the normal group and between the days of induction of benign prostate hyperplasia during two months. It reveals that there is a stable state of serum inflammatory cytokines during induction of benign prostate hyperplasia in dogs.