Had the referee, Steve Tanner, been on the ball victory might have been more comfortable for the Canaries, but because he missed two clear-cut penalties it was left to an own goal from Danny Rose and a Gary Doherty header to give the home fans the victory their singing deserved.
The home side kicked off attacking the Barclay End goal and created a shooting chance within seconds, but Scott Loach beat away Dave Mooney's acute angled drive.
The visitors escaped a penalty with a blatant handball offence. Norwich then forced five corners in quick succession without testing Loach, but in the 15th minute he was beaten by one of his own players.
In dispossessing Jon Otsemobor on the edge of his penalty area, Rose succeeded in lifting the ball over his keeper and into the bottom corner of the net.
At the other end Will Hoskins hit a long-range shot which rattled the city crossbar, when play switched to the visitors' end, Alan Gow's shot was deflected for a corner and Darel Russell fired over.
The Hornets, clearly stung by their half-time team talk, put the Canaries under pressure at the start of the second half until Norwich broke away and Gow was only inches away with a low angled drive.
Mr Tanner seemed to have taken a dislike to Alan Lee and booked him when Adrian Mariappa went down in dramatic fashion.
In the 65th minute Sammy Clingan went close with a well hit volley and Lee hit the post with a thunderous left-foot drive.
Jon Harley then cleared Jason Shackell's header off the line.
Lee appeared to receive the ball from a Watford player and ran forward to score, but a late offside flag cut short the City celebrations.
However, victory was assured when Shackell's header from Clingan's right-wing corner came back off the bar and Doherty planted his firm header inside the near post.