Background: Effect of seasonal variations in human fertility has been intensively researched; some studies acknowledge influences of seasonal changes on natural conception while others cannot confirm them. The aim of this study was to assess the presence of a possible Seasonal pattern in the functional parameters of Semen samples.Materials and Methods: This study was carried out on 335 Semen samples that were collected and analyzed according to the average highest temperature of the Normo-spermic men between January 2019 and December 2 014 at the Fertility Center in Al- Sadr medical city. Najaf Iraq.Results: ALL Semen Parameters displayed trends opposite to average highest temperature variations. Semen volume, sperm concentration sperm motility and normal sperm morphology were significantly lower (p<0.05) in summer than other seasons of the red year: Semen volume sperm concentra and normal sperm morphology was found to be statistically significantly higher in the winter (p<0.05). The percentage of sperm motility was a significantly (p<0.05) is higher in spring The highest values of Semen volume sperm concentration and sperm morphology was recorded in January and February, while a higher sperm motility was found during the march any of the year.Conclusion: We observed that was significant effect of season on the semen parameters. Highest environment temperature may be a determining factor for the seasonal variations in semen quality.