The invention discloses a multistage full-hydraulic-regenerative solar seawater desalinization device and relates to the technical field of seawater desalinization devices. The seawater desalinization device comprises heat collection units of 7 stages which are arranged sequentially, wherein the heat collection unit of a first stage comprises 8 heat collecting tanks which are in series connection sequentially, each heat collecting tank comprises a seawater tank, a seawater inlet and a saline water outlet, a heating pipe is arranged in each seawater tank, a heat pipe evaporation section is arranged in each heating pipe in a penetrating manner, one end of each heating pipe is connected with the corresponding seawater tank through a sealing bolt and a sealing gasket, one end, far away from the corresponding sealing bolt, of each heat pipe evaporation section penetrates through a seawater tank wall and then is connected with a heat pipe condenser pipe, the periphery of each heat pipe condenser pipe is wrapped with a full-glass heat collecting pipe, and the heat pipe condenser pipes and the full-glass heat collecting pipes are arranged on CPCs (Compound Parabolic Concentrators). The seawater desalinization device achieves the aims that the structure is simple, the efficiency of seawater desalinization is high, and the water making performance coefficient of the device is remarkably increased.