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Aim and background: Asthenozoospermia is one of the most common reasons of infertility in men, which is known as low or no movement of sperm. The purpose of the present study is to clarify the relationship between polymorphism rs1893316 of gene Catsper1 with Asthenozospermia in men. Materials and methods: The present molecular study, After filling in the consent form by both 50 control and 50 experimental groups, 2ml blood was taken, then DNA isolated through salting out method and sequencing procedure was used to specify polymorphism. Result: In studying polymorphism rs1893316 C>T CC genotype frequnency and TT genotype frequnency was considerably higher in control group than experimental one(P<0.05). In hetrozygotic genotype CT frequency, there wasn't a significant difference between experimental and control group(P>0.05). Discussion: Catsper1 channel physiologically is limited to sperm movement path, following it, the release of calcium ion and imbalance in ionic density leads to sperm movement increase regarding both it's strength and speed. Conclusion: There is a meaningful relation between polymorphism rs1893316 gene Catsper1 with Asthenozoospermia. The result may change with a change in genetic treasury in the participants or meaningful change in population size.