Seventy-five cases of chronic prostatitis were treated with intraprostatic injection of azactam via transperineal route. Direct intraprostatic antibiotic injection was advantageous. The drug can cross the barrier of the lipoprotein epithelial membrane of the prostate with a high concentration in the gland and longer effects. Of the 75 patients, 73 (97.3%) were cured. The pharmacological properties of azactam are also described.