A multilayer substrate includes a laminate, signal conductors, and external connection conductors. The signal conductors are at different positions in a lamination direction of the laminate. The external connection conductors are provided on a back surface of the laminate. A first signal conductor is connected at one end to one of the external connection conductors by a first wiring conductor. A second signal conductor is connected at one end to one of the external connection conductors by a second wiring conductor. The first signal conductor is closer to the back surface than the second signal conductor. The first wiring conductor includes wiring adjusting conductors each having a length corresponding to a distance difference in the lamination direction between the first and second signal conductors.