The current study aimed to determine the fertility parameters among BPH patients before and after 3 months of taking 5-α reductase (finasteride) by seminal fluid analysis method, 60 patients and 30 healthy individuals as control group from Amara city ,were involved in this study, their ages were between (40-59)year old. They all subjected to direct seminal fluid analysis before and after 3 months of treatment by 5α-reductase(finasteride)(the healthy individuals didn’t take finasteride).The results showed that there is significant decreasing in volume (P˂0.05) in post-treatment group compared to pre-treatment and control group ,while the concentration of semen (count and total count) found to non-significantly decrease in post-treatment compared with pre-treatment and decreases significantly (P˂0.05) in comparison to control control group. On other hand, the Motility(high, moderate) observed to non significantly decreased in post-treatment group compared to pre-treatment group ,but significantly decreased (p<0.05) compared to control group, The Morphology(normal and abnormal ) found to non significantly differences between pre-treatment group and post-treatment group, but that were significantly differences in control group compared to pre-treatment and post-treatment group. Concluded that BPH affects on fertility parameters. Keywords: BPH. fertility. semen, finasteride