The visitors almost snatched the lead after just 19 seconds but veteran keeper Mark Crossley denied Ian Craney with a superb stop.
But he was left with no chance when the Huddersfield new boy came up with a scoring breakthrough on the half hour. The 26-year-old - signed from Accrington last month - hit an angled drive from six yards for his second goal in five games.
Kelvin Lomax, Chris Taylor and Lee Hughes should all have made Town keeper Matt Glennon work harder with first-half efforts, but Oldham made no mistake for a leveller in the 49th minute.
The lively Taylor was brought down by Jim Goodwin 25 yards out and a well worked free kick between skipper Mark Allott and Andy Liddle saw the veteran winger rifle home his third goal of the season.
In a nail-biting finish Hughes shot straight at the keeper in the 85th minute and Huddersfield's Michael Flynn did the same at the opposite end with two minutes to go.