Starfish are mainly oviparous, but some of them can reproduce asexually. Most starfish are dioecious. These starfish have gonads. After breeding, their glands will become very large and even fill the whole wrist. Its germ cells can stimulate ovulation and sperm excretion, and when combined, fertilized eggs can be produced. Asexually reproducing starfish usually produce male germ cells at an early age, and then produce female cells when they grow up, and then combine.

1. Dioecious: Most starfish belong to this type. This starfish usually has 10 gonads, which are composed of some grape-like tubes. The gonads of male starfish are generally white, while those of female starfish are generally orange. They can produce germ cells. In the breeding period of starfish, females will lay eggs, while males will produce sperm, and spawning and fertilization are carried out in seawater. These fertilized eggs undergo cleavage, develop blastocysts, and then gastrula, at which time they can begin to swim freely. After that, they will slowly develop into complete starfish.

2, hermaphrodite: There are relatively few hermaphrodite starfish, and they reproduce in different ways. Generally speaking, when Haixinghai is relatively young, male germ cells are produced first; When they grow up, they will then produce female germ cells. These two types of germ cells can combine and reproduce.