Hairtail is an oviparous fish on the grass, and the gonad of 10 months old is mature, so it is difficult to distinguish between male and female. Generally, male fish is smaller and longer than female fish. The breeding water temperature is 2 degrees Celsius higher than usual, the pH is ph6.5--6.8, the hardness is 3-4, the water is clear and fresh, the aquatic plants are placed, and the most important thing is to avoid the light absolutely, and the black cloth should be used to cover it. Generally speaking, in the morning, the male fish begins to turn around the female fish to show their courtship, and then both swim near the aquatic plants and begin to lay eggs. The number of eggs laid by female fish is less than 150, so fertilized eggs must develop in the dark and avoid light. The parent fish should be fished out after spawning to prevent swallowing eggs.