A resin multilayer substrate includes a stacked body including resin layers, a component, one or more first conductor patterns, and one or more second conductor patterns each disposed in a gap between the resin layers. At least a portion of an outline of each of the one or more first conductor patterns overlaps with the component. An outline of each of the one or more second conductor patterns does not overlap with the component. A resin portion is adjacent to each of the one or more first conductor patterns along a portion of the outline of each of the one or more first conductor patterns that overlaps with the component. The resin portion is made of a resin paste including thermoplastic resin powder as a main material. The resin portion is not disposed in a portion along the outline of each of the one or more second conductor patterns.