Jakob Chychrun and Josh Bailey each had a goal and an assist for the Senators.
Connor Hellebuyck made 30 saves for the Jets, who finished the preseason 2-3-1.
Claude Giroux gave Ottawa a 1-0 lead on a breakaway at 16:58 of the first period.
Bailey, who is with the Senators on a professional tryout agreement, scored off a rebound in the slot at 17:26 of the second period to make it 2-0.
Chychrun scored a power-play goal at 10:28 of the third period for the 3-0 final.
