Isaac Sinclair's first-half strike proved the difference between the two sides at the Wham Stadium, as the hosts claimed their first league win of the season at the expense of the U's.
Colchester produced an improved second-half display after a disappointing first half but their day was compounded in the closing stages when winger Owura Edwards was shown a straight red card for a late challenge on Accrington goalkeeper Ollie Wright.
Colchester boss Danny Cowley made four changes to his starting line-up for the Accrington game.
Jack Baldwin, Harvey Araujo and Dominic Gape all made their first league starts for the U’s, while Kyreece Lisbie was also brought into the starting line-up with Jack Tucker skippering the side.
Harry Anderson, Josh Powell and Teddy Bishop dropped out as did skipper Tom Flanagan, who missed out due to injury.
Accrington started well and Charlie Brown's curled effort from the right edge of the area was pushed away by U’s goalkeeper Matt Macey, inside the opening two minutes.
Tyler Walton fired a low shot wide of the far post for the hosts while Brown just failed to connect with Paddy Madden's deflected effort in the U's six-yard box, as Accrington pushed for an opener.
Brown fired a first-time effort wide after Isaac Heath had curled the ball dangerously into the U's box, before Macey made a brilliant fingertip save midway through the first half to push Heath's effort over for a corner, after the Accrington left winger went on a sparkling run and weaved his way past several defenders.
_(Image: Richard Blaxall)_
Colchester registered their first meaningful effort on goal in the 27th minute when Lisbie's curled effort from the edge of the area flashed just wide of the far post.
But Accrington took a deserved lead in the 32nd minute through Isaac Sinclair, who raced onto Brown’s through ball and converted past Macey, who was hurt in the challenge.
After several minutes of treatment, Macey was replaced by Tom Smith between the sticks.
Colchester had a glorious chance to equalise on the stroke of half-time when Lisbie blasted over with the goal at his mercy from six yards, following some fine work by Owura Edwards on the left wing, as the U’s went in at the break behind.
_(Image: Richard Blaxall)_
Colchester made a double change at the break, with Jaden Williams and Josh Powell introduced for Baldwin and Jack Payne.
The U's improved in the second half and began to enjoy more territory and possession, without really testing goalkeeper Wright.
Bishop, Micah Mbick and JK Gordon were all sent on in the second half as Colchester hunted an equaliser but their task was made much harder when they were reduced to ten men in the 86th minute after Edwards was shown a straight red card for a late challenge on goalkeeper Wright.
_(Image: Richard Blaxall)_
The hosts were able to see the game out to claim victory and extend the U's winless league run to five matches.
**MATCH STATS: Colchester United:** Macey (sub Smith, 37), Hunt, Tucker, Baldwin (sub Powell, 46), Araujo, Read (sub Bishop, 57), Gape, Lisbie (sub Gordon, 62), Payne (sub Williams, 46), Edwards, Tovide (sub Mbick, 62).
**Substitutes (not used):** Vincent-Young.
**Accrington Stanley:** Wright, Sinclair, Ward, Matthews, Brown (sub Love, 62), Walton, Bauress, Smith, Conneely (sub Coyle, 82), Heath, Madden (sub Caton, 46).
**Substitutes (not used):** Henderson, Martin, Woods, Kelly.
**Referee:** Martin Coy.
**Goals:** Accrington: Sinclair (32).
**Bookings:** Colchester: Araujo (foul, 45), Gape (foul, 60), Williams (unsporting behaviour, 70). Accrington: Smith (foul, 31), Love (unsporting behaviour, 70).
**Sending off:** Edwards (serious foul play, 86).
**Attendance:** 2,107 (199 U's fans)