An electronic control apparatus for a vehicle according to the present invention includes: an electronic control board which electrically controls respective parts in the vehicle; a connector which is electrically connected with the electronic control board; an extruded housing which is opened at both sides, and has one side into which the connector connected with the electronic control board is inserted and accommodated in a slot manner; a connector cover which is coupled to the connector and covers the one open side of the extruded housing into which the connector is inserted; and a back cover which covers the other open side of the extruded housing, in which a first potting layer is formed at an upper side of the connector cover, and a second potting layer is formed in the back cover adjacent to the other side of the extruded housing.