The invention discloses a floating type sea wave energy conversion device which is used for mainly solving the problems that an energy collector is easy to have one-way deflection due to the fact that a hauling cable is directly connected with the energy collector, the efficiency conversion is low and stable energy output cannot be obtained. The floating type sea wave energy conversion device comprises a base, a generator, a hydraulic motor, the energy collector and an energy converter, wherein a fixing rod is arranged on the base; the fixing rod comprises an annular gear part and an optical shaft part; a gear matched with the annular gear part is arranged at the energy collector, a hauling cable winding wheel is arranged at one shaft end of the gear, and the energy collector is sleeved on the optical shaft part for moving up and down; the energy converter comprises a cylinder body, a piston, an end cover and the hauling cable; the hauling cable is connected between the piston and the hauling cable winding wheel, a guide column sleeved with a spiral spring is arranged between the end cover at the lower end of the energy collector and the piston, and the guide column penetrates through the end cover and is matched with the end cover with interval. The gear matched with the annular gear part is used for driving the piston for executing reciprocating motion through the hauling cable, the energy conversion efficiency is improved and stable energy output can be obtained.