The teams entered half time goalless but quick fire goals Sam Dalby and Hector Kyprianou gave the O’s a two-goal lead, before Dalby notched a second and Teddy Perkins sealed the victory.
Youth Team coach Danny Webb made two changes to the XI that were defeated by Stevenage on the weekend.
Ruel Sotiriou and Hector Kyprianou were introduced to the side in place of Jaedon Phillips and Amin Benyoucef who suffered with an ankle injury midweek.
A slow start the game saw possession shared between the sides, before Ruel Sotiriou went down under a challenge in the area and the O’s were awarded a penalty.
Sam Dalby stepped up to take the spot kick but the AFC Hornchurch ‘keeper Callum Calder was equal to it and palmed it to safety.
Since the chance from the spot, Orient looked the more likely of the two teams to open the scoring, Charles Clayden’s series of whipped crosses provided trouble for Calder early on, the best chance came when Lopes attempted to poke the ball towards the net but it wasn’t enough to beat the ‘keeper.
Sotiriou went close just after 20 minutes of play, when he forced his way in to the box and fired at Calder, but the ‘keeper parried the shot in to the path of Lopes whose effort was blazed over from close range.
Moments later, Dalby broke in to the area on the wide right and drilled a low cross in to Sotiriou who was positioned at the far post, but he couldn’t connect with the ball to direct it goal-wards.
It was one-way traffic as Sotiriou done well to shake off his marker and enter the area one-on-one with the ‘keeper, but Calder reacted well to deny the striker’s effort.
The visitors registered their first shot on target on the stroke of half-time when Armando Quitirna curled a left footed shot towards goal only to be denied by an excellent save from Arthur Janata in the Orient goal.
As both teams returned for the second-half The Urchins were the first side to make a change and almost instantly Orient took the lead through Dalby who tapped in from close range after Calder had saved the initial shot from Sotiriou.
Moments later Kyprianou added a second when he stroked the ball home after he had collected Dalby’s through ball wide inside the area.
Dalby notched his second goal of the game with just over 20 minutes of play left. Lopes scoped the ball over Jake Jolliffe before Dalby beautifully stroked the ball in to the top corner with the outside of his boot.
Again, Orient continued to attack well in all areas as Clayden fired over from close range after good link up play between Andrew Camilo-Tayaca and Sotiriou.
Teddy Perkins connected with a Clayden corner only to see his effort cleared off the line for another corner by Charlie Arnold, but the captain got his goal seconds later when he headed home Lopes’ set-piece.
The O’s will now host Biggleswade Town in the First Round, with further information to be announced in due course.
ORIENT: Arthur Janata, Andrew Camilo-Tayaca, Toby Stevenson, Teddy Perkins, Alfie Fleming, Ernold Haxhiu (Luca Carter-Henry 79), Eric Lopes, Hector Kyprianou, Charles Clayden, Ruel Sotiriou (Jaedon Phillips 79), Sam Dalby
SUBS: Samuel Amedu, William Sanders, Brendon Shabani
GOALS: Dalby (47 & 68), Kyprianou (52), Perkins (76)
BOOKED: Clayden (27), Kyprianou (88)
AFC HORNCHURCH: Callum Calder, Tyrone Baker (Dale Ashman 45), Shadrach Ogie, Charlie Arnold, Jake Jolliffe, Courtney Justin (Jahvlen Martin 69), Dylan Singh, Sam Brown, Johnny Knight (Toby Barlow 63), Michael Gyasi, Armando Quitirna
SUBS: Harry Lambert, Joe Strange
BOOKED: Baker (11), Gyasi (21)