Electronic control device

An electronic control device comprising:

• a circuit board including a wiring board bearing a wiring pattern including a high-speed signal line, and an electronic component mounted on a first surface of both surfaces of the wiring board, the electronic component being electrically connected to the high-speed signal line;
• a case housing the circuit board;
• and
• a first heat conductive member in direct contact with the electronic component and with the case, wherein
• the electronic component has a bottom surface facing the first surface of the wiring board, an upper surface located opposite to the bottom surface, and an outer peripheral surface connected to an outer edge of the bottom surface and to an outer edge of the upper surface, and wherein
• the first heat conductive member is disposed in such a way as to extend from the upper surface of the electronic component to the case and to extend from the first surface of the wiring board to the case while being in contact with a part of the outer peripheral surface of the electronic component at a position at which the first heat conductive member avoids a space above the high-speed signal line.