The result means the Hornets remain the only side without a win in the Premier League so far this season, while the visitors have not secured all three points since September 20.
Watford had the best of the early chances, although were unable to find the net with the absence of striker Danny Welbeck apparent as they struggled to find an outlet during their attacking moves.
Bournemouth have now failed to score in their last three Premier League matches, and have 13 points from their first 10 matches of the season, while Watford remain rooted to the bottom of the table.
— Watford Football Club (@WatfordFC) October 26, 2019
The sides have now played out seven draws in their nine recent meetings in the Premier League.
The visitors continued to grow into the game and had opportunities on the counter-attack, in the 22nd minute Ben Foster had to dive low and save a strike from Philip Billing.
Just after the half hour mark, Bournemouth almost took the lead when the ball fell to Diego Rico at the edge of the area, and he superbly hit a half-volley which Foster was only just able to get down and make another save.
The hosts started the second half in the same way they started the first, with Deulofeu forcing Ramsdale into a save inside the opening two minutes, after expertly weaving through the box.
The second 45 minutes lacked the end-to-end momentum of the first, with the wind and rain falling as neither side were able to create any clear-cut chances.
Watford, lacking a natural striker up front, tried to make up for it by bringing Andre Gray on at the hour mark, but the change did not have the desired effect as they were still unable to find the breakthrough.
With less than 10 minutes left, the Hornets came agonisingly close to scoring when Roberto Pereyra flicked on a corner which was deflected just ahead of the arriving Gray at the far post.
Bournemouth substitute Harry Wilson came close at the other end from a free-kick just outside the box, curling the ball over the wall and just wide of Foster’s goal as the points were shared.