Villa remain in fight for fourth
Gabriel Agbonlahor's smart finish inside the box gave Villa the lead on 14 minutes but Kevin Kilbane missed a great chance to equalise for the hosts.
Hull striker Jan Venegoor of Hesselink was carried off on a stretcher in the second half following a clash of heads and James Milner added a penalty for Villa 12 minutes from time.
"We're in the mix. We're going for everything and guaranteed nothing," Villa manager Martin O'Neill told reporters.
"Where I've been pleased with the team is they've responded fantastically to the defeat at Stamford Bridge.
"The team has shown a great deal of character all season and I think that was epitomised tonight."
Villa moved above Liverpool into sixth on 61 points from 35 matches and trail Tottenham Hotspur, who occupy the fourth and final Champions League qualifying spot, by three having played one game more.
Hull, in 18th place with 28 points, are three points adrift of safety with just three games left.