The Robins were knocked out of the FA Cup despite a Ryan Jackson goal as Alvechurch's Danny Waldon scores in both halves.
The eighth-tier side had the opening opportunity of the match, Tyrell Skeen-Hamilton firing a central free-kick over the bar from 25 yards out.
Moments later, the first chance for the Robins fell to James Olayinka, who picked the ball up 30 yards from goal, but his curled shot from the edge of the box deflected wide for a corner.
Olayinka came close again, Ryan Broom making space for himself down the right channel, pulled his cross back to Olayinka on the penalty spot, whose shot went past the right post.
Cheltenham kept the pressure on the visitor’s goal, Caleb Taylor forcing ‘keeper Daniel Jezeph into a diving save to his right with a header from close range.
Alvechurch took the lead against the run of play, Waldron picking up the loose ball before taking on a defender on the edge of the box and slotting the ball past Southwood.
Wade Elliott was forced into a change after half an hour, with the injured Ben Williams having to be replaced by Dan Nlundulu. The striker’s presence was quickly felt as his footwork won a corner resulting in another Taylor header just missing the goal.
The substitute was then inches away from connecting with a well created George Lloyd shot with three minutes to go in the half.
It was Olayinka again who had the next Robins chance. Broom setting the midfielder up from close range, but was denied again by a save from the inspiring Jezeph.
Alvechurch and Waldron got their second of the game early in the second half. The forward bundling the ball over the line after it rebounded off the post from Concannon shot on the top of the box.
The two goal deficit was short lived as Ryan Jackson replied moments later. A cross from the left evaded all in the box, with the wing-back firing in a volley into the far bottom corner of the goal from eight yards out.
In the pursuit of the equaliser, Alfie May and Christian Norton were brought onto the pitch. The latter instantly finding space down the right, setting up Broom, but the Welshman fired his shot over the bar.
The Robins had seemingly equalised when Norton headed in Taylor’s ball back across the goal from close range. However neither the referee or linesman deemed the ball crossed the line.
The Robins ended the game with 10 men, as goal scorer Jackson had to be removed due to injury.
Cheltenham Town XI: Southwood, Long, Williams(39’ Nlundulu), Freestone, Sercobe, Taylor, Adshead(May 69’) , Lloyd (Norton 45’), Jackson, Broom, Olayinka, (Brown,)
Cheltenham Town unused substitutes: MacDonald, Raglan, Bradbury, Bonds, Chapman
Alvechurch XI: Jezeph, Burton, Sephton, Neto-Tiexiera, Willits, Carter, Abbey, Adge, Concannon (Williams 74’), Waldron, Skeen-Hamilton (Brown 89’)
Alvechurch unused substitutes: Behan, Cassidy, Williams, Taylor, Wooley, Hallahan
Referee: R. Lewis
Attendance: 4446 (1423)