A method for forming thermally conductive composition on electronic components comprises three steps, (I) preparing a silicone composition comprising (A) a polyorganosiloxane, (B) a thermally conductive filler and (C) a catalyst, (II) applying the silicone composition on an electronic component of electronic devices, the electronic component generates heat when the electronic devices are working and (III) curing the silicone composition by heat generated by the electronic component.