The invention discloses a saprolegniasis prevention and control method for gymnocypris potanini. The method includes the steps that A, a flowing water breeding barrel is needed, flowing water breeding is performed, and ammonia nitrogen is controlled below 0.05 mg / L; B, water flow is controlled, wherein the speed of flowing water is controlled through a water pump or by adjusting the direction and the magnitude of water flow of a water inlet; C, throwing for feeding is performed, wherein after temporary raising and food domesticating, rainbow trout juvenile fish feed is thrown for feeding; D, drug use is performed, wherein the water amount is measured and calculated according to the area of a pond and the water depth, and oxytetracycline is splashed; E, vitamins are used, wherein vitamin C is splashed in the whole pond; and F, saprolegniasis prevention and control are performed for parent fish after delivery, wherein after hormone injection and spawning induction for egg squeezing, under the water temperature of a breeding season, and on the basis that daily prevention and control is kept, prevention and control measures include that a, soaking of glucose and a triphosadenine solution is performed after delivery; and b, antibiotics are thrown for feeding, wherein ampicillin is added in each kilogram of feed, and after stirring and uniform mixing, throwing for feeding is performed. The method is easy to execute, and easy and convenient to operate, effectively prevents generation of saprolegniasis in the breeding process of the gymnocypris potanini and after spawning induction, and a basis is laid for the species protection work of the gymnocypris potanini.