Laboratory fish are small in size and caliber, and their microdiet has limited uses because of poor stability, food inductivity, digestibility and water pollution. In contrast, live food is appropriately sized, rich in nutrition, and does not pollute the water quality; thus, it has long been recognized as the main feed for laboratory fish. Herein, we review the biological characteristics; nutrient composition; possible pathogens, toxins, and harmful substances; and quality control indexes of live food, such as Paramecium caudatum, Brachionus plicatilis and Artemia salina, which are commonly consumed by laboratory fish, to provide a quality control reference for laboratory fish feed.