A substrate interconnection structure comprising: a first substrate; a second substrate disposed opposite the first substrate at a predetermined distance therefrom; a connector (3, 25, 45) secured to the first substrate; a connection object (5, 23, 43) with a housing (9, 26, 46) and secured to the second substrate, the connection object being electrically connected to the connector; wherein the connector includes an engagement-side housing (8, 28, 58) engaged with the connection object, a substrate-side housing (7, 27, 57) secured to the first substrate, and a first terminal (11, 30, 50) having a first contact portion (11e, 30e, 50e) in electrical contact with the connection object (5, 23, 43) engaged with the engagement-side housing (8, 28, 58) and a movable piece (11c, 30c, 50c) elastically connecting the engagement-side housing (8, 28, 58) to the substrate-side housing (7, 27, 57); and when at least one of the first substrate and the second substrate warps in engaging and disengaging directions of the connection object with respect to the engagement-side housing (8, 28, 58), the movable piece (11c, 30c, 50c) elastically supports the substrate-side housing (7, 27, 57) displaced in response to movement of the first substrate, while maintaining the contact of the first contact portion with the connection object, characterized in that the substrate interconnection structure further comprises: a spacer formed neither by the connector's housings (7, 8, 27, 28, 57, 58) nor by the connection object's housing (9, 26, 46), the spacer attached at the surfaces of the first and second substrates and positioned between said first and second substrates in an engaged state between the connector and the connection object, a substrate interconnection structure being formed by keeping the distance between the substrates and constant. a first substrate; a second substrate disposed opposite the first substrate at a predetermined distance therefrom; a connector (3, 25, 45) secured to the first substrate; a connection object (5, 23, 43) with a housing (9, 26, 46) and secured to the second substrate, the connection object being electrically connected to the connector; wherein the connector includes an engagement-side housing (8, 28, 58) engaged with the connection object, a substrate-side housing (7, 27, 57) secured to the first substrate, and a first terminal (11, 30, 50) having a first contact portion (11e, 30e, 50e) in electrical contact with the connection object (5, 23, 43) engaged with the engagement-side housing (8, 28, 58) and a movable piece (11c, 30c, 50c) elastically connecting the engagement-side housing (8, 28, 58) to the substrate-side housing (7, 27, 57); and when at least one of the first substrate and the second substrate warps in engaging and disengaging directions of the connection object with respect to the engagement-side housing (8, 28, 58), the movable piece (11c, 30c, 50c) elastically supports the substrate-side housing (7, 27, 57) displaced in response to movement of the first substrate, while maintaining the contact of the first contact portion with the connection object, characterized in that the substrate interconnection structure further comprises: a spacer formed neither by the connector's housings (7, 8, 27, 28, 57, 58) nor by the connection object's housing (9, 26, 46), the spacer attached at the surfaces of the first and second substrates and positioned between said first and second substrates in an engaged state between the connector and the connection object, a substrate interconnection structure being formed by keeping the distance between the substrates and constant.