The invention discloses a vacuum drying device for powder metallurgy. The vacuum drying device comprises a cylinder and further comprises a top cover, wherein the top cover is used for condensing steam as well as draining and exhausting steam condensate; the cylinder and the top cover are connected in a sealing manner so as to form a closed cavity; the top cover comprises a top cover inner wall, atop cover outer wall and a cooling medium circulation channel; the cooling medium circulation channel is positioned on an interlayer between the top cover inner wall and the top cover outer wall; thetop cover inner wall takes the shape of a cone or a sphere of which the middle protrudes upward; a cooling medium inlet and a cooling medium outlet are formed on the top cover outer wall and both communicate with the cooling medium circulation channel; a condensate collecting tank used for collecting the steam condensate is arranged below the edge of the top cover inner wall; a pipeline used forexhausting the steam condensate in the condensate collecting tank is connected onto the condensate collecting tank; and a recycling barrel is connected with the output end of the pipeline. The vacuumdrying device disclosed by the invention has the advantages that the drying efficiency is high, the liquid residue is low, the rapid batched drying process can be achieved, and the purity and the quality of powder obtained from the drying process are high.