In this paper, a new kind of cryoprotectant-Dimethyl formamide (DMF) is be-ing reported that it has a significant effect on cryopreservation for freshwater fish sperm. The ferti-lizing rates of thawed sperm in blunt snout bream, common carp, grass carp, silver carp andbighead carp are 76%, 54.03%, 68.6%, 37.9% and 40.6%, respectively. Using 10-15% DMF ascryoprotectant and 0.5% NaCl in extender were available 2%NaCl as active solution and 10times volume of active solution to dilute thawed sperm during fertilization were necessary.