New signing Robert Koren went close on three occasions for the Tigers from long distance, but the hosts had goalkeeper Matt Duke to thank for preserving a clean sheet as he denied Danny Graham and Jordon Mutch after the break.
Jay Simpson went straight into the Hull starting XI after joining from Arsenal, while Watford manager Malky Mackay named the same line-up for the third Championship match in a row.
Watford carved out the first opening of the contest when Will Buckley brushed aside Paul McShane and cut infield, but his curling effort drifted wide.
Koren and Simpson then combined at the other end, with the former just failing to pick out the latter with a superb cross.
The hosts began to build some pressure, and Koren went close minutes later when he forced Scott Loach into a flying save with a left-footed shot from the edge of the area.
Simpson then fired into the side-netting following McShane's deep cross, but with little separating the two sides in a mediocre encounter, Hull started resorting to ambitious efforts.
The early stages of the second half were similarly stop-start, but Koren demonstrated his ability from long range again with a dipping volley just over from 20 yards.
The visitors should have taken the lead though when Martin Taylor headed wide from six yards following Don Cowie's inswinging free-kick from the left flank.
Mackay tried to shake things up with a double substitution as Troy Deeney and Mutch came on to replace Marvin Sordell and Buckley, respectively.
Hull continued to look marginally more threatening though, as Tom Cairney drilled an angled drive across the face of goal and then substitute Mark Cullen scuffed a shot from a good position.
Deeney failed to make the most of a decent opening for Watford as he headed wide from close range after Cowie had picked him out with a pinpoint cross.
However, Duke was forced into action moments later when he tipped wide Graham's snap-shot from 18 yards.
Koren was easily the most creative player on display, and he went close for a third time in the match with a cross from the left wing that nearly sneaked in at the far post.
As the clock ticked down, the game finally started to open up, but a lack of cutting edge continued to frustrate at both ends.
Nick Barmby's cross was headed wide by the unmarked Richard Garcia as Hull tried to commit more men forward.
Watford nearly snatched a late winner when a low half-volley from Mutch was parried by Duke, but the contest always seemed certain to end goalless.