The invention discloses a seawater domestication method for Daphniopsis tibetana Sars, which comprise the following steps: disinfecting the culture container, culture container being opaque in periphery; concocting culture liquor, taking disinfected and filtered seawater to adjust pH value to 7-8, temperature 10-15 degree, salinity 10-15, selecting Daphniopsis tibetana Sars and placing it in container, culturing it with above-mentioned liquor, illumination intensity 1000-2000Lx, photoperiod 14D:10L, feeding with Chaetoceros sp. feedstuff, feeding volume 30x105cell / ml, selecting healty, activefemale Daphniopsis tibetana Sars which has produced baby Daphniopsis tibetana Sars and is 2-3 mm in body length, feeding it with algae liquid selecting one or two kinds from Chaetoceros sp., Dunaliella salina, Isochrysis galbana, chlorella, feeding density 30x105cell / ml, inoculating Daphniopsis tibetana Sars density 100ind / l, observing Daphniopsis tibetana Sars growth state and water body to partly for wholly substitute for Artemia and promote fish fry survival rate, reduce the seedling-breeding cost.