Alexis Sanchez and Mesut Ozil were on target as Arsenal scored three times in four minutes after the break to gallop away from a Huddersfield side who had recovered well having fallen behind to Alexandre Lacazette's early opener.
Olivier Giroud came off the bench to score twice as Arsenal remained in fourth place, 12 points behind leaders Manchester City and two ahead of fifth-placed Liverpool.
The margin of victory flattered Arsenal, although the quality of their finishing was sublime.
"The last 20 minutes became comfortable but I would say Huddersfield did fight very well," manager Arsene Wenger said.
"In the second half I felt at some stages it could have been 1-1 but when we scored the second goal the game changed completely. We played very well, with freedom. We played a bit on the edge before that."
Lacazette scored his seventh league goal of the season after three minutes, tucking home after a superb flick by Aaron Ramsey. The one blot on the evening for Arsenal, however, was a groin injury that prevented Lacazette appearing after the break.
Huddersfield were still in the game but Ozil and Sanchez combined to tee up Giroud for a tap-in in the 68th minute before Ozil found Sanchez who volleyed home.
Ozil capped a great display to beat exposed Huddersfield keeper Jonas Lossl from Ramsey's assist.
French striker Giroud completed the rout last on from close range as Arsenal warmed up for Saturday's home clash with Manchester United in impressive fashion.
Huddersfield dropped to 14th place, having also been beaten by Manchester City at the weekend, but manager David Wagner was not too worried.
"We have had two defeats, they probably shouldn't be a surprise to anybody but we learn from these defeats and we are mentally strong enough to put this behind us," he said.
(Reporting by Martyn Herman, editing by Ed Osmond)
