The invention belongs to the technical field of maritime engineering equipment, and discloses a semisubmersible aquaculture net cage, comprising an underwater floating body, a center upright column, main upright columns, secondary upright columns, surrounding pull rods and a fishing net, wherein two or more main upright columns are fixed on the underwater floating body, surround the center upright column in the middle, and are connected by virtue of supporting rods; two or more secondary upright columns surround the center upright columns in the middle, and are connected with the center upright columns by virtue of the supporting rods respectively; the main upright columns are connected with the main upright columns or the secondary upright columns on the two sides respectively by virtue of the surrounding pull rods; the secondary upright columns are connected with the main upright columns or the secondary upright columns on the two sides respectively by virtue of the surrounding pull rods; and the fishing net is spread out in the space surrounded by the main upright columns, the secondary upright columns and the surrounding pull rods, and is fixed on the main upright columns, the secondary upright columns and the surrounding pull rods. The net cage provided by the invention is strong in stormy wave resistance and strong in aquaculture capacity stability.