Abstract: Objective:To investigate the clinical effects of diosmin combined with α-blockers in the treatment of type Ⅲ B prostatitis.Methods:Two hundred patients with type Ⅲ B prostatitis were randomly divided into the control group and observation group(100 cases each group).The control group and observation group were treated with tamsulosin and diosmin combined with α-blockers,respectively.The chronic prostatitis index score(NIH-CPSI),international index of erectile function score(ⅡEF-5) and quality of life score(QOL) between two groups before and after treatment were compared.The curative effects in two groups were evaluated,and the occurrence of adverse reactions in two groups were observed.Results:Before treatment,the differences of all item scores between two groups were not statistically significant(P>0.05).Compared with before treatment,the NIH-CPSI score and QOL score in two groups decreased,and the ⅡEF-5 score increased after treatment.After treatment,the NIH-CPSI score and QOL score in observation group were lower than those in control group,and the ⅡEF-5 score in observation group was higher than that in control group(P<0.05 to P<0.01).The total effective rate in observation group(90%) was significantly higher than that in control group(70%)(P<0.05),and the difference of the incidence rate of adverse reactions between two groups was not statistically significant(P>0.05).Conclusions:Diosmin combined with tamsulosin in treating type Ⅲ B prostatitis can significantly improve the patient's sexual function and quality of life,which has good effect and mild adverse reactions.