Chelsea had chances to win it in the second half, but Watford goalkeeper Huerelho Gomes made good saves from Branislav Ivanovic substitute Eden Hazard and Diego Costa.
The result means Chelsea are unbeaten in 10 matches, but Guus Hiddink’s side still sit 13th while Watford moved up a place to ninth.
“I think we were worth a win tonight,” caretaker manager Hiddink said.
“In the second half we were in control and even in the last 20 minutes we deserved to win.
“I think Gomes will be the man of the match.”
Hiddink said the good thing is that his side are improving, even if they are still drawing too many games.
“We are playing every week better and better,” he said. “My old goalie from a previous spell, Gomes, got a big reward. If not, we would have won easily.”
Gomes said he was delighted with the team’s performance and his own display.
“The players worked so hard in the first half,” Gomes said.
“It was difficult because Chelsea are getting better and better but it was a good performance from the team and a good one for myself.
“I believe we are working well, working hard every game, the boys are pushing so much and that’s why we are in the position we are in.”
In the night’s other game, Everton climbed to 11th after a 3-0 victory over third-bottom Newcastle.
Aaron Lennon put the home side ahead after 23 minutes and the winger set up the second when he was fouled in the area, with Barkley scoring from the spot.
In the fourth minute of injury time, Jamaal Lascelles was sent off for Ross Barkley in the penalty area and the England midfielder dinked in the penalty.