A substrate mounting structure comprising: a substrate member including a substrate portion (Bd), the substrate portion (Bd) having a first surface (Sa) and a second surface (Sb) opposite to each other in a thickness direction of the substrate portion (Bd), first to fourth edges (eg1, eg2, eg3, eg4), and a predetermined thickness (h1) in the thickness direction; a first mounting member on which the substrate member is placed; and a second mounting member attached to the first mounting member to hold the substrate member on the first mounting member , wherein: the first mounting member includes a first restricting portion (Se1) abutting on the first edge (eg1) to restrict movement of the substrate member , a second restricting portion (Se2, Se3) abutting on the second edge (eg2) to restrict movement of the substrate member , and a third restricting portion (Sk1, Sk2) abutting on the second surface (Sb) to restrict movement of the substrate member in the thickness direction; and the second mounting member includes a fourth restricting portion (Sf2) abutting on the third edge (eg3) to restrict movement of the substrate member , a fifth restricting portion (Sf3) abutting on the fourth edge (eg4) to restrict movement of the substrate member , and a sixth restricting portion (Su1) abutting on the first surface (Sa) to restrict movement of the substrate member . a substrate member including a substrate portion (Bd), the substrate portion (Bd) having a first surface (Sa) and a second surface (Sb) opposite to each other in a thickness direction of the substrate portion (Bd), first to fourth edges (eg1, eg2, eg3, eg4), and a predetermined thickness (h1) in the thickness direction; a first mounting member on which the substrate member is placed; and a second mounting member attached to the first mounting member to hold the substrate member on the first mounting member , wherein: the first mounting member includes a first restricting portion (Se1) abutting on the first edge (eg1) to restrict movement of the substrate member , a second restricting portion (Se2, Se3) abutting on the second edge (eg2) to restrict movement of the substrate member , and a third restricting portion (Sk1, Sk2) abutting on the second surface (Sb) to restrict movement of the substrate member in the thickness direction; and the second mounting member includes a fourth restricting portion (Sf2) abutting on the third edge (eg3) to restrict movement of the substrate member , a fifth restricting portion (Sf3) abutting on the fourth edge (eg4) to restrict movement of the substrate member , and a sixth restricting portion (Su1) abutting on the first surface (Sa) to restrict movement of the substrate member . the first mounting member includes a first restricting portion (Se1) abutting on the first edge (eg1) to restrict movement of the substrate member , a second restricting portion (Se2, Se3) abutting on the second edge (eg2) to restrict movement of the substrate member , and a third restricting portion (Sk1, Sk2) abutting on the second surface (Sb) to restrict movement of the substrate member in the thickness direction; and the second mounting member includes a fourth restricting portion (Sf2) abutting on the third edge (eg3) to restrict movement of the substrate member , a fifth restricting portion (Sf3) abutting on the fourth edge (eg4) to restrict movement of the substrate member , and a sixth restricting portion (Su1) abutting on the first surface (Sa) to restrict movement of the substrate member . <EOS>