An electronic control apparatus includes housing members, and a circuit board. At least one of the housing members is opposed to a heat-generating region which is heated by the heat-generating electronic component. A heat radiating portion of the housing member includes a convex portion protruding from an inner wall surface at a location opposed to the heat-generating region, and a concave portion opened to an outer wall surface at a location shifted from the convex portion in a thickness direction. The convex portion is close to the heat-generating region through a clearance. The concave portion has a lateral wall formed in a tapered shape such that an opening area of the concave portion is larger than a bottom area of the concave portion. A thickness of the heat radiating portion is smaller than a thickness of a region peripheral to the heat radiating portion in the housing member.