The invention aims at providing a semi-submersible type tide power generation device, which comprises a main floating body, main floating tubes, two horizontal side wings, side wing floating tubes, a generator, generator cabins, an impeller, two rotary frames, a hinge and a hinge machine, wherein the two horizontal side wings are arranged at two sides of the main floating body, the two horizontal side wings and the main floating body form a cross shape, two ends of the main floating body are respectively provided with the main floating tubes, side wing floating tubes are respectively arranged on the two horizontal side wings, generator cabins for installing generators are respectively connected onto the two horizontal side wings through respective vertical connecting wings, the impeller is connected with the generator, the hinge machine is arranged on the main floating body, the two rotary frames are respectively arranged on shafts of the two side wing floating tubes, one end of the hinge is connected with the hinge machine, and the other end of the hinge is connected with the rotary frames. The semi-submersible type tide power generation device has the advantages that the structure is simple, the production and manufacture cost is low, the installation and the maintenance are convenient and economic, the power generation performance is stable, and the semi-submersible type tide power generation device is suitable for being applied to high-sea-condition environment with rich tide energy.