Wednesday substitute Sergiu Bus opened the scoring in the 86th minute but Ishmael Miller, also on as a substitute, secured a point for the visitors with an equaliser just a minute from time.
The result leaves Huddersfield without a win in their last seven games and 18th in the table, six places and nine points behind Wednesday.
Huddersfield’s Marnick Vermijl sent in an early low cross that evaded everyone, and Wednesday striker Caolan Lavery fired in a fierce angled shot that went over.
The hosts had another chance when Lewis McGugan tried a shot from the edge of the area that went wide.
Huddersfield responded with Joel Lynch firing in a shot on the turn that forced a near-post save from Keiren Westwood.
Just a few minutes before the break, the visitors carved out another good opening when, following a scramble, David Edgar got in a shot that was cleared off the line by Vermijl.
Six minutes after the restart, Wednesday’s Atdhe Nuhiu looked certain to score. He received the ball from Kieran Lee, rounded keeper Alex Smithies and rolled the ball towards the unguarded net, only to see Lynch race back to clear off the line.
Wednesday were down to 10 men for a spell when Joe Mattock went off injured. After receiving some lengthy treatment, the defender returned to the field with his head bandaged.
Lavery sent a shot off-target after losing his balance and then went down inside the area with Reece James in close attention, but referee Mark Haywood was unimpressed.
Wednesday head coach Stuart Gray made a double substitution just after the hour mark, with strike duo Stevie May and Bus replacing Lee and Nuhiu.
Huddersfield manager Chris Powell also made an attacking change shortly after, sending on Miller in place of Nahki Wells.
Miller was soon involved, making a promising run into the area before having a shot blocked when he could have passed to a team-mate.
Wednesday substitute Bus also had a chance to make a quick impact when he had time inside the area, but his low shot lacked the necessary power to test Alex Smithies, who gathered easily.
Miller made another good run into the area and made an unsuccessful appeal for a penalty when he went down under a challenge.
Wednesday substitute Chris Maguire’s free-kick was on target but failed to cause a problem for Smithies.
Bus scored to put the hosts in front, following up to turn the ball home from close range after his initial effort was kept out.
But with just a minute to go in normal time, Miller scored the equaliser after finding himself in space inside the area.