This invention is to provide an electronic substrate device which is capable of reliably and stably transferring heat generated by a heat generating component to a base member serving as a heat dissipater without intermediation of an electronic substrate. An electronic substrate device according to the present invention, in which a base member (10A) includes a central protruding portion (15A) which is accommodated in a penetrating portion (32A) while facing a die pad (42A) through an intermediation of a first gap (G1), and first separated protruding portions (17a and 17b) which are provided around the central protruding portion (15A) and have a height dimension smaller than that of the central protruding portion (15A), the first separated protruding portions (17a and 17b) having a top surface which abuts a rear surface portion of the electronic substrate (30A) to form a second gap (G2), and in which a first heat transfer bond (16A) which is a heat conductive adhesive is applied to the first gap (G1) and the second gap (G2) communicating with the first gap (G1).