The invention discloses a heat-conducting plastic cement and a moulding method thereof. Nylon PA6 / PA66 is used as a base material of the heat-conducting plastic cement. The heat-conducting plastic cement is prepared by mixing aluminum nitride AlN, silicon carbide SiC, silicon trioxide Al2O3, graphite, fibrous high-thermal-conductivity carbon powder and scaly high-thermal-conductivity carbon powderwhich are used as fillers; wherein the nylon PA6 / PA66 accounts for 50 to 60wt%, the aluminum nitride AlN accounts for 3 to 5wt%, the silicon carbide SiC accounts for 4 to 6wt%, the silicon trioxide Al2O3 accounts for 5 to 8wt%, the graphite accounts for 10 to 15wt%; the fibrous high-thermal-conductivity carbon powder accounts for 6-10wt%; the scaly high-thermal-conductivity carbon powder accountsfor 6-10wt%. The moulding method of the heat-conducting plastic cement comprises the following steps: A, drying the heat-conducting plastic cement materials, wherein heating for 4-6H at the temperature of 110-130 DEG C for later use; B, by adopting following parameters, carrying out injection molding at the mold temperature of 60-100 DEG C, and the material temperature at 240-300 DEG C; the backpressure of 1-3 atmospheric pressures. Due to the application of the technical scheme, the product manufactured by the invention has the advantages of good heat-conducting property, low specific gravity and good portability; and the production period is short, insulation treatment is not needed, and the production cost is low.