Purpose : Comparison of effectiveness of tamsulosin combined with minirin and tamsulosin alone in treatment of BPH patients Inclusion and exclusion criteria : International prostatic symptom score more than 7 , 3 or more episodes of nocturia , abillity to providing time-urine volume chart were among the inclusion criteria . Surgical indication ,post voiding residue more than 200 cc , history of ischemic heart disease were the exclusion criteria . Method :354 patients with benign prostatic hyperplasia were randomized in to group A and B . Patients received tamsulosin plus minirin in group A and tamsulosin alone in group B . After 2 months , minirin was omitted from regimen of group A and added to regimen of group B .It continued for another 2 months . Patient were evaluated initially , 2 months and 4 months after study started respect to International Prostatic Symptom Score , nocturia , post voiding residue , peak flow rate , prostate volume , bladder wall thickness , nightly urine volume .Evaluations were done by sonography , uroflowmetry , time-voiding volume chart and International Prostatic Symptom Score questionnaire.