Mysis shrimps lay eggs and are fertilized during mating. After the eggs are laid, they are held in the brood sac on the female's chest and develop. The shape of the newly hatched larvae is similar to that of adults, only lacking a pair of thoracic limbs.

Many species of mysid shrimp can live in low salt water or brackish water. Many species live a planktonic life, but many species inhabit and move on the seabed, often diving into the sediment on the seabed. Most species live in shallow seas, and many species are native to deep seas. Most species are omnivorous and live mainly by filtering organic debris from the water. There are also carnivorous species. Mysis shrimp reproduce and grow rapidly in the warm season, and can mature and lay eggs in one week. Some species form large groups in shallow seas or near estuaries, and fixed nets are often produced in large quantities offshore. It has high nutritional value and delicious taste. It can be eaten fresh or fermented into shrimp paste, and can also be used as feed for farmed fish and shrimp.

This order is divided into 2 suborders: ① Lophogastrida, which has only two families, Lophogastridae and Lophogastridae. They are mostly deep-water species and breathe through the gills of the thoracic limbs; ② Mysida suborder (Mysida), *** 4 families: Mysidae (Mysidae), Lepidomysidae (Lepidomysidae), Petalophthalmidae (Petalophthalmidae), Mysid shrimp family (Stygiomysidae). Breathe through the soft tissue inside the cephalothorax.

Some species of shallow-water mysids (especially Neomysids and Mysids) are abundant in large quantities, such as black and brown Mysids in the Yellow and Bohai Seas, Neomysids orientalis, and Mysids longus. Shrimp and other species have important economic value.