Callum Harriott's early strike - in what was just his second start - won the game for the Addicks, who picked up their eighth away win of the season.
After the high of Tuesday's dramatic 2-1 win over Middlesbrough when two late goals earned them the three points, this was a real comedown for the Terriers, who struggled to create chances throughout.
Bristol City's win over Middlesbrough means Huddersfield are just five points clear of the npower Championship relegation places, while their goal difference of minus 25 makes for grim reading.
Both sides were unchanged from midweek with Mark Robins able to select Anthony Gerrard, who recovered from the Achilles problem which forced his early withdrawal from Tuesday's win over Middlesbrough.
After Tuesday's heroics, today could not have started much worse for the home side.
After three minutes Charlton were ahead. A short free-kick from Chris Solly on the left of the area found an unmarked Harriott, who fired past Alex Smithies and into the corner.
It was a sluggish start from Huddersfield and it was not until the 15th minute when they created their first decent opportunity when Oscar Gobern's near-post header went wide.
Town were starting to have more of the ball and after 27 minutes they almost levelled as David Button had to show good reaction to direct Theo Robinson's powerful headed effort away from danger.
Four minutes later and the visitors were thankful of Michael Morrison's quick reactions, as the centre-half managed to clear the ball from inside the six-yard box when Lee Novak was set to pounce.
Charlton always looked dangerous on the break and Danny Haynes should have at least tested Smithies with a header from Lawrie Wilson's cross.
The striker did however force a good save from the stopper seconds later. Harriott raced through the Huddersfield midfield and his excellent through ball found Haynes, who struck a decent effort to Smithies' right with the keeper pushing his effort to safety.
Charlton were now creating chances at will and Wilson's near post flicked header from a Johnnie Jackson free-kick was cleared off the line by a stretching Peter Clarke.
In added on time, Oliver Norwood's swerving effort had Button in trouble, but he managed to claw the ball away to safety.
With Huddersfield struggling to get the ball to stick up front, Robins decided to act.
He brought on strikers Alan Lee and Danny Ward - who both scored against Boro on Tuesday - for Robinson and Norwood after 55 minutes, with Clayton moving into the middle as Town went 4-3-3.
The changes lifted both the crowd and the players as they upped the tempo in a bid to find the equaliser.
Midfielder Dorian Dervite replaced striker Ricardo Fuller after 66 minutes as Chris Powell looked to repel Huddersfield's pressure.
The extra defensive cover worked as Huddersfield couldn't break down the visitors.
Scott Arfield was introduced with 10 minutes left to provide a much-needed creative spark, but it did not come as Huddersfield lost at home for the fifth time this season.
- Sports & Recreation
- Callum Harriott
- Alex Smithies