A thermosoftening and heat conductive silicone grease composition including: (A) a silicone wax having a melting point of 30-80° C.; (B) a organopolysiloxane indicated by formula R1aSiO(4-a)/2 (R1 indicating a monovalent hydrocarbon group and a being 1.8≤a≤2.2) and having a kinematic viscosity of 10-500,000 mm2/s at 25° C.; and (C) a heat conductive filler material having a heat conductivity of at least 10 W/(m·K).