Smith ran 53 yards for a touchdown on the second play of the third quarter to give the Jets a 10-7 lead, then went 89 yards with a kickoff return in the fourth period to put New York in front by 14 points.
The Jets advanced to 9-2 with their fourth straight victory and kept pace with New England atop the division. The Patriots won earlier in the day with a dominating second half of their own against Detroit. Cincinnati lost its eighth in a row and fell to 2-9.
Mark Sanchez completed 16-of-28 passes for 166 yards and threw a 13-yard scoring pass to Santonio Holmes late in the third quarter that gave the Jets a 17-7 advantage.
Aaron Pettrey kicked a field goal for the Bengals in the fourth period to cut their deficit to 10, but Smith returned the ensuing kickoff for the score that wrapped up the victory.
Carson Palmer was 17-of-38 for the Bengals, picking up just 135 yards and throwing two interceptions.