Tangerines boss Jason Aldcroft gave a first full start to Alex Titchiner with Mark Beech, Connor Tierney and Kyle Jones all returning to the starting line-up following the midweek home loss to Porthmadog.
The first chance fell to in-form Gresford striker Jake Eyres who had a great chance early on but he put his shot wide. The Tangerines should of been ahead when Connor Tierney fed in Alex Titchiner who turned his marker and hit a shot on the angle that agonisingly beat the keeper but hit both posts and bounced out.
Conwy's uncertain defence conceded after 10 mins from a corner kick when Jack Challinor was afforded a free header and he took advantage to find the back of the net.
The lead was doubled when a cross into the box was met by Jake Eyres to make it 2-0. It could of been worse minutes later but Jake Roberts skied it over from close range a few minutes later.
The third goal came when a ball into the box was failed to be cleared and Gresford winger Craig Pritchard, who had been a constant thorn in the Tangerines defence all game, took advantage and fired his effort inside the box into the top corner.
Conwy had a chance to pull a goal back as Titchiner played a lovely ball into Bigland to put him through on goal but his shot was blocked by Gresford keeper Jon Dunt for a corner and the score remained 3-0 going into the half time.
The pace of the game dropped down somewhat in the second half with the home side content with letting Conwy have the ball for long spells. In a half of few chances the best fell to Gresford who had a header cleared off the line. The fourth goal arrived on 80 mins when the ball was given away outside the box by the Conwy defence which allowed Gresford sub Owen Roberts to advance on goal and unleash an unstoppable shot into the top corner.
The Tangerines had a chance to grab a consolation in the final minutes when Titchiner's flick fed substitute Joe Chaplin but his run and shot ended up just wide of the post.
After a second consecutive defeat, Conwy Borough drop to 11th in the table after 8 games played and now need to re-group ahead of a tough visit to Holywell next Saturday.