The Hornets had the better of the chances though and Chris Eagles, Alhassan Bangura and Marlon King might all feel they should have beaten Boaz Myhill.
The visitors shaded a rather sedate opening period, but the Hull keeper made his first good save of the game when he grabbed Eagles' low drive after the winger had cut inside.
Soon after, Eagles got free on the right again but his pull-back was completely missed by Darius Henderson and King blazed wide.
Watford continued in the ascendancy and almost made the breakthrough on two occasions, both chances coming from Lloyd Doyley long throws.
First, Henderson's header was easily saved by Myhill, but then the Hull keeper had to go to ground to turn another header from the Hornets striker behind.
However, the Tigers had an opening of their own in the last minute of the half when Stuart Green's well struck 20-yard shot forced a good save from Ben Foster.
Hull started the second half on the front foot and almost scored when Gavin Mahon dallied in midfield and his eventual pass was intercepted and played through to sub Darryl Duffy, but his low drive was impressively kept out by Foster.
Leon Cort then sent a free header badly wide, but Watford then took charge again with Henderson just unable to direct an excellent King cross on target.
A goal looked inevitable with 15 minutes remaining when Bangura exchanged passes with King and burst into the area, but again Myhill saved, as he did when some impressive trickery from King created a chance from nothing, but his stinging half-volley was beaten away by the Hull keeper.