The invention discloses a land batch-type seedling collecting method for porphyra haitanensis. Firstly, heat exchange is adopted, the water temperature is lowered, spore bag branch dual division is promoted, then, when some spore bag branches are subjected to dual division, porphyra haitanensis shell protonema can be transplanted into a sink of a seedling collecting waterwheel, the water temperature of the waterwheel sink is controlled to be 27 DEG C or below to promote spore diffusion, and a net with the area about 200 m<2> is hung to each waterwheel with the diameter being 2 m so as to ensure uniform shell spore seedling attaching; every morning is the shell spore spreading peak, when the each 10*10 view on a microscopic examination seedling rope reaches 15-30 h or longer, and seedlingsare collected when the requirement for the seedling collecting density is met. According to the seedling collecting method, on the basis of waterwheel type seedling collecting, the characteristic thatporphyra haitanensis shell protonema can release shell spores while being mature is sufficiently utilized, porphyra haitanensis land batch-type seedling collecting is achieved on the shell spores, the shell spore utilization rate is effectively increased, and the seedling raising yield is increased; meanwhile, the net curtain underground time can be scattered, and the labor intensity is lowered.