An electronic control device of the invention having a multiple of power supply system lines, with an object of providing a device such that no circulation path is formed in a ground line, includes a power supply in which a multiple of power supply system lines are provided, a multiple of drive units to which the power is independently supplied from the power supply system lines, and at least one controller that outputs control signals to the multiple of drive units, and is configured so that negative side lines of the power supply system lines are connected by one ground line in the controller.