Boyd pounced after just 68 seconds and, despite a battling display by the home-side, Huddersfield's three-match winning run was ended.
Boyd scored the only goal in Leyton Orient's victory at Huddersfield last season and was also on target for previous club, Hartlepool, and his early effort was enough to secure a third win in four matches for the visitors.
Huddersfield have struggled at home this season, winning just twice in eight league matches and were refused three penalty shouts and it clearly wasn't their night.
The Huddersfield defence was caught cold by Sean Thornton's clever ball over the top and Boyd was there to fire home.
Orient, now unbeaten in five matches, were difficult to break down and have now kept six clean sheets in seven matches.
Huddersfield had efforts from distance from Ian Craney and Jim Goodwin, before Gary Roberts was denied by Stephen Purches and then Phil Jevons was blocked by a great saving tackle from Tamika Mkandawire.
Joe Skarz saw a bullet header go just wide before Michael Collins also missed the target.
Huddersfield thought they had a good appeal for a penalty ten minutes before the break when Mkandawire appeared to handle the ball as he went down.
After the break it was all one-way traffic but Huddersfield could not make the breakthrough.
Skarz and Roberts set up Collins, but again he was wide of the mark and then Roberts lashed over acrobatically as Town failed to test keeper Glenn Morris.
On the hour Huddersfield had another penalty appeal waved away when Alton Thelwell appeared to bring down Roberts just inside the box, but referee Chris Sarginson was having none of it.
Nathan Clarke twice went close with headers before substitute Danny Broadbent had the best chance to equalise but he blazed over in stoppage time.