Liam Delap's late strike finally found a way through Huddersfield's stubborn rearguard to make it three wins from four for Hull.
The Manchester City loanee struck as the game moved into added time just when it seemed a fighting effort from the Terriers would earn them a second successive goalless draw.
Delap had hit the bar minutes earlier, in a game of few chances, but snapped up his late opportunity to give Hull a much-needed fillip after they lost at West Brom last week.
Defeat leaves Huddersfield with just one win in their last 10 games to leave them one place and four points above the relegation zone while the three points boosts Hull to the fringes of the play-off places.