Steve Claridge's fourth goal in two games earned Portsmouth three precious points in their battle against relegation.
The veteran striker's 74th-minute header from a Ceri Hughes left-wing free-kick sailed past Nico Vaesen in a rare threat on the Belgian keeper's goal.
It was Pompey's second victory of Tony Pulis' brief reign as manager after a Claridge hat-trick sent Barnsley crashing at Fratton Park last week.
Huddersfield, fielding a make-shift strikeforce of new signing Martin Smith and midfielder Dean Gorre with Clyde Wijnhard suspended and Marcus Stewart having left for Ipswich, had numerous chances to break the deadlock.
But a combination of poor finishing and some fine goalkeeping from Pompey custodian Russell Hoult kept the Terriers at bay.
In the sixth minute Smith flashed a left-foot shot from a tight angle past Hoult's right-hand post after getting between ex-Bradford man Darren Moore and Michael Panopoulos.
The former Sheffield United favourite then sent a left-foot shot into Gorre but the Dutchman's looping header was gathered by Hoult.
On 18 minutes Gorre had a goal ruled out for offside by the referee before a right-foot drive from Norman Slater took a deflection of Smith's boot to fall into Hoult's grasp.
Portsmouth's chances were few and far between but Lee Bradbury did try his luck with a long-range drive on nine minutes and a fierce effort on 20 which flew wide of Vaesen's post.
Barry Horne fed Craig Armstrong with a low centre towards Gorre in the 30th minute and the midfielder skimmed Hoult's left-hand post with a first-time effort.
Then Jamie Vincent sent a deep cross which Gorre met with his head but Hoult pulled off a superb block before Thomas Thogersen cleared as Smith prepared to pounce on the loose ball.
But Huddersfield struggled for chances in the second period, though Jenkins did manage a first-time volley just on 47 minutes.
Smith struck the woodwork from a Chris Holland cross on 61 after Gorre had linked with the Huddersfield new boy.
And on 65 minutes Ben Thornley spurned a glorious chance when he cleared Hoult's upright from a George Donis cross.
Town were then rocked as a rare foray from Portsmouth resulted in the visitors taking the lead on 74 minutes.
Portsmouth won a free-kick on the left flank and Hughes curled in an inch perfect cross for Claridge.
His bullet header sailed into Vaesen's right-hand corner to the delight of the visiting fans behind the goal.
Huddersfield introduce Delroy Facey in a desperate effort to find an equaliser but Portsmouth closed ranks to take all three points back to the south coast.