NOVELTY - A heat-conductive silicone adhesive composition comprises 100 parts mass organopolysiloxane (A) having alkenyl group which is coupled with at least two silicon atoms in a molecule, 0.01-30 parts mass liquid organohydrogenpolysiloxane (B) including skeleton of polysiloxane containing a cyclic structure, 5-4000 parts mass thermal-conductive filler (C), hydrosilylation reaction catalyst (D), 0.1-100 parts mass organopolysiloxane (E) including skeleton of polysiloxane which does not contain cyclic structure and 0.01-10 parts mass acetylene black (F).    USE - Heat-conductive silicone adhesive composition is used for reactor (claimed) for battery set-up converter. Uses include but are not limited to hybrid electric vehicle, plug-in hybrid electric vehicle, electric vehicle and fuel cell vehicle.    ADVANTAGE - The silicone adhesive composition has high thermal conductivity, fluidity, adhesiveness with respect to metal and organic resin and physical property after hardening, and provides reactor with high reliability.    DETAILED DESCRIPTION - A heat-conductive silicone adhesive composition comprises 100 parts mass organopolysiloxane (A) having alkenyl group which is coupled with at least two silicon atoms in a molecule, 0.01-30 parts mass liquid organohydrogenpolysiloxane (B) including skeleton of polysiloxane containing a cyclic structure, in which at least one epoxy group is coupled with a silicon atom through alkylene group (excluding alkoxy group) and 2-10 hydrogen atoms are coupled with silicon atom in a molecule, 5-4000 parts mass thermal-conductive filler (C), hydrosilylation reaction catalyst (D) in an amount to promote curing of the composition, 0.1-100 parts mass organopolysiloxane (E) including skeleton of polysiloxane which does not contain cyclic structure but has at least one silyl group of formula: -SiR1aR23-a (1) in a molecule, and 0.01-10 parts mass acetylene black (F) obtained by thermally decomposing acetylene. The viscosity of component (A) is 0.05-1000 Pa.second at 25 degrees C. The viscosity of component (B) is 100 mPa.second or less at 25 degrees C. The polymerization degree of polysiloxane in component (B) is 15 or less. The viscosity of component (E) is 0.01-30 Pa.second at 25 degrees C. The bulk density of acetylene black is 0.06-0.18 g/cm3. The molar ratio of silyl (SiH) group of component (B) and alkenyl group of component (A) is 0.2-5.    R1=optionally substituted monovalent hydrocarbyl;    R2=1-8C alkoxy or acyloxy;and    a=0, 1 or 2.    An INDEPENDENT CLAIM is included for reactor, which is potted using the heat conductive silicone adhesive composition.