An insulating thermally conductive resin composition (10) includes a matrix resin (1) and insulators (2). The insulators (2) are dispersed in the matrix resin and have electrical insulation. The insulating thermally conductive resin composition further includes a thermally conductive phase (3) which has a hither thermal conductivity than the matrix resin and thermally connects the insulators with each other. The thermally conductive phase (3) is composed of an organic substance. The thermally conductive phase that thermally connects the insulators is composed of the organic substance, so that the resultant insulating thermally conductive resin composition has electrical insulation while having improved thermal conductivity.