The invention discloses a method for preparing and storing fruiting dunaliella algae paste, and belongs to the field of aquaculture. Preparation of fruiting dunaliella algae paste is mainly finished by algae fluid centrifugation of a centrifugal machine or algae cell precipitation of a single precipitant in the past, so that the preparation method is high in power consumption, high in cost, poor in sedimentation efficiency, long in sedimentation time and incomplete in precipitation. In order to overcome the defects in a traditional technology, the algae fluid is participated and concentrated by adopting the compound precipitant, so that the method is complete and fast in participation, low in expense, short in elapsed time, and simple and convenient to operate. A composite cryoprotectant is adopted, and a method for gradually cooling is adopted in the cryopreservation process of the algae paste, so that the method disclosed by the invention is simple in process, easy to grasp, small in harm to cells, and high in cell survival rate; the nutritional ingredients are not lost basically; and the storage time can be up to 5 years, and is much higher than 2-3 years of the traditional storage method.