Ethan Hamilton scored an 89th-minute goal to earn Lincoln their first win under new boss Michael Skubala.
Hamilton collected a pass from Lasse Sorensen and wrong-footed Orient keeper Sol Brynn to clinch the points in this rearranged fixture that proved a drab affair.
Hakeeb Adelakun should have scored five minutes earlier when he broke free down the right but with only the keeper to beat, he screwed his shot wide of the far post.
Four minutes later, Imps shot-stopper Lukas Jensen came to the rescue when he threw himself at a Ruel Sotiriou effort.
The visiting keeper had produced a fine double save in the first half to deny Brandon Cooper before getting down quickly to deny Aaron Drinan who seized on the loose ball.
Both sides were industrious but failed to generally find the spark or flair necessary to extend opposition defences.
There was little change in the pattern of play after the break and it was not until the closing stages that the game sprung into life.
Orient had been leading 1-0 in the original fixture on October 3 when the fixture was abandoned after 82 minutes due to a medical emergency when Os fan Derek Reynolds suffered a cardiac arrest and was treated pitchside.
Sadly, it was announced the following day that Reynolds had died. The rearranged fixture was preceded by a minute’s silence in his honour.
