The utility model discloses a mold structure of a floating sliding block. The mold structure comprises a limiting column, a sliding block mold core, a cylinder, a guide column, a guide sleeve, a sliding block, a central guide track and a sliding block base, wherein the guide sleeve is arranged at the outer end of the guide column; the sliding block mold core is connected with the tail end of the sliding block; the sliding block is connected with the cylinder; a baffle block is arranged at the outer end of the sliding block mold core; a product is sleeved upon the sliding block mold core; the central guide track is arranged at the upper end of the sliding block; the guide column is extended into the sliding block, so as to ensure that the sliding block mechanism is precisely guided in the floating process; a bronze guide sleeve is embedded on the sliding block mold core. The utility model provides a typical floating type sliding block mechanism, the product can be transversely arranged and no thimble is needed to be designed, the phenomena that a mold is too high when the product is vertically arranged and thimble trace can be caused on the surface of the product when being transversely arranged are solved, the service life of the mold is prolonged, the mechanical action of the mold is feasible, and the mold structure is high in representativeness.