Coventry goalkeeper Joe Murphy produced a string of fine saves to help his relegation-threatened side contain in-form Watford.
The hosts went close early on when John Eustace crossed for Sean Murray, who headed over unmarked from six yards.
Eustace wasted another great chance just before the break, side-footing wide from similar range.
Murphy made a double save after 75 minutes, blocking a Troy Deeney effort then keeping out a Eustace strike.
This was a welcome result for Coventry, who had suffered 10 successive away defeats before this match, but their search for a first Championship away win of the season continues.
The visitors had started the brighter but Watford created the better chances. Eustace played a one-two with left-back Carl Dickinson before crossing for Murray, who headed off target.
Watford went close once more when Alex Kacaniklic swung in a corner and Britt Assombalonga glanced a header narrowly over Murphy's crossbar.
Coventry's Nathan Cameron thought he had headed the visitors into the lead from a Gary McSheffrey corner, only for referee Colin Webster to rule it out for a push at the near post.
McSheffrey was starting to look threatening and his cross picked out Clive Platt, whose powerful downward header forced Adrian Mariappa to clear off the line. But the visitors had an escape themselves when Eustace squandered his opportunity.
Watford pressed hard in the second half as Murphy was forced into a fine save from Deeney's drive from the edge of the area. That was followed by the Coventry goalkeeper's impressive two saves in quick succession.
VIEWS FROM THE DRESSING ROOM
Watford manager Sean Dyche told BBC Three Counties Radio:
"You've got to be thinking on the positive side - it's another point gained, another clean sheet.
"It was an awkward game. These teams are fighting for their lives.
"They killed the game constantly and the referee played his part in that, which was disappointing for us and disappointing for our fans because they want see free-flowing games, they want to enjoy themselves - and it definitely had an effect on the game.
"In the first half, we were just off it, not as bright as we have been, in the second half, there was a good reaction. We created one or two excellent chances."