Kit Symons, who was handed the full-time job last week, saw goals from Hugo Rodallega, Lasse Vigen Christensen and Ross McCormack see off the Terriers.
It was rough on the visitors, who dominated for long periods and looked the more likelier to win the game after drawing level via Joel Lynch with 15 minutes remaining.
Huddersfield are a side transformed under a new manager of their own in Chris Powell, having lost just once in their last eight games before arriving in west London.
Their confidence showed in their blistering start as Mark Hudson’s header from Paul Dixon’s fourth minute corner was cleared off the line by Scott Parker.
The West Yorkshire side were presented with another chance in the 16th minute which should have been converted. Harry Bunn broke free unchallenged but dragged his near post shot the wrong side of the post.
Fulham have looked shaky at the back in recent weeks but have been scoring goals for fun. And they were at it again to make Huddersfield pay three minutes later.
McCormack fed Rodallega who slotted past Huddersfield goalkeeper Alex Smithies for the 19th minute opener.
The opening goal seemed to settle Fulham down – and had an adverse effect on the Terriers.
George Williams saw his clipped shot go inches wide with Smithies beaten. And the Welshman almost carved out a second goal of the afternoon for Rodallega on the stroke of half-time.
Williams’ clever lob saw Rodallega just fail to keep his header down from close-range.
Powell must have had some choice words with his players as Huddersfield began like a different team after the restart.
Bunn once again lost his radar when well placed before Jacob Butterfield fired his 25-yard shot into the side-netting.
Fulham were finding themselves pegged back but they almost scored against the run of play as Smithies foiled Rodallega in the 55th minute.
Errors were creeping in with the driving rain and a mistake allowed Dixon to nip in where his cross-shot was cleared off his own line by Konstantinos Stafylidis.
It seemed a matter of when, rather than if, that Huddersfield would draw level. Another chance went begging when Grant Holt somehow blazed over from Dixon 65th minute free-kick.
But that equaliser came via Lynch in the 75th minute. Dixon’s set-piece delivery was again spot on and Lynch beat goalkeeper Marcus Bettinelli to head home.
Fulham responded by regaining their lead just two minutes later through Christensen.
The midfielder nut-megged Hudson and lifted the ball over the advancing Smithies for a fine solo goal.
Rodallega wasted a golden chance to kill off Huddersfield when he shot over late on. But McCormack’s 25-yard strike with six minutes to go clinched the win.