An electronic circuit device according to the present invention includes a base substrate having a wiring layer, at least one first electronic circuit element having a first surface fixed to the base substrate and having a connection part on a second surface opposed to the first surface, a re-distribution layer including a photosensitive resin layer, the photosensitive resin layer enclosing the first electronic circuit element on the base substrate and embedding a first wiring photo via, a second wiring photo via, and a wiring, the first wiring photo via electrically connected to the connection part of the first electronic circuit element, the second wiring photo via arranged at the outer periphery of the first electronic circuit element and electrically connected to a connection part of the wiring layer, the wiring arranged on the second surface and electrically connected to the first wiring photo via and the second wiring photo via.