A resin-sealed electronic controller obtained by bonding and fixing a circuit board to a thermally-conductive base plate, and integrating circuit components with a molding resin so as to reduce the size. A base plate includes a first exposed portion, a second exposed portion, and an adjacent flat portion adjacent to a central window hole. First circuit components which are low-heat-generating components with large height are located in the central window hole. Second circuit components which are high-heat-generating components with small height are provided on an area corresponding to the adjacent flat portion. A height dimension of the first circuit components at least partially overlaps a thickness dimension of the base plate, to reduce a total thickness dimension. The high-heat-generating components and the low-heat-generating components being provided separately from each other permits increased mounting density of low-heat-generating components, reducing an area of the circuit board.