To provide an outboard motor capable of enhancing exhaust purification efficiency.

An outboard motor includes a housing 34 leading exhaust generated in an engine thereinside. The inside of the housing 34 is demarcated into a first exhaust space S1 and second exhaust space S2 by a partition wall 33e. The first exhaust space S1 is connected to a plurality of exhaust ports and collects exhaust introduced from a plurality of exhaust ports to be led from the bottom to the top. The second exhaust space S2 is connected to the first exhaust space S1 and situated on the same side as the first exhaust space S1 with respect to a plane including central axes of respective cylinders. The catalyst 35 is positioned at a height such that at least a portion of the catalyst 35 overlaps with the first exhaust space S1 when viewed from a horizontal direction, and arranged in the second exhaust space S2 so as to lead exhaust led from the first exhaust space S1 to the second exhaust space S2.