An engine control apparatus includes an apparatus body, and a control lever. The apparatus body includes a housing, an axis unit including a drive gear, a driven gear, and an angle sensor. A plurality of fixing portions are provided on the housing. A through-hole is formed in the fixing portion. The through-hole is communicated with a first side wall and a second side wall of the housing. The housing is fixed to a port-side mounting surface or a starboard-side mounting surface by a screw member inserted into the through-hole. When the control lever is operated, the drive gear and the driven gear are rotated in accordance with an angle of operation. A rotational angle of the driven gear is detected by an angle sensor.