The two sides had initially been due to lock horns on January 7, but the match was postponed following a pitch inspection at the Bolt New Lawn Stadium, which led to a new date being set.
Match preview
Forest Green have had to win twice to reach this stage of the competition, beating South Shields 2-0 on November 5 before recording a 2-1 victory over Alvechurch at the end of the month.
Ian Burchnall's side will enter this match off the back of a 1-1 draw with Exeter City in League One on Saturday, which ended a four-game losing run in England's third tier.
The Green, who were League Two champions last season, are currently bottom of the League One table, having only picked up 21 points from their 26 matches during the 2022-23 campaign.
Burchnall's team are only three points behind 20th-place Morecambe, though, so it is not quite time to hit the panic button despite their struggles for results in recent weeks.
Forest Green will not view the FA Cup as a priority competition this season, but it could act as a welcome distraction from their league troubles, and they will be facing a Birmingham side short on confidence due to their recent struggles in the second tier of English football.
Indeed, Birmingham will enter this contest off the back of a four straight losses in the Championship, including a 4-2 defeat at Bristol City on Saturday afternoon.
John Eustace's side are currently 18th in the second tier, six points above the relegation zone, having collected 32 points from their opening 27 matches of the season.
Birmingham have never won the FA Cup, but they have been in two finals in this competition, finishing as runners-up in both 1930-31 and 1955-56.
The Blues were beaten by West Bromwich Albion in the 1931 final before losing to Manchester City in 1956, but it would be a huge shock if they were able to challenge for the trophy this season.
Birmingham have two more Championship matches before the end of the month, facing Preston North End and Norwich City, but they will be bidding to avoid what would be a shock third-round exit to Forest Green.
Forest Green Rovers FA Cup form:
W
W
Forest Green Rovers form (all competitions):
W
L
L
L
L
D
Birmingham City form (all competitions):
D
W
L
L
L
L
Team News
Forest Green head coach Burchnall will need to assess the fitness of his squad following the 1-1 draw with Exeter in the league on Saturday afternoon.
However, the third-tier side have not reported any fresh injuries, so it is likely to be a similar squad for this game.
There will be changes from the side that started at the weekend, with Regan Hendry and Amadou Bakayoko likely to be named in the starting XI.
Birmingham, meanwhile, will again be missing Harlee Dean and Przemyslaw Placheta through injury.
The Blues did not suffer any fresh fitness issues against Bristol City, but head coach Eustace is expected to make changes to his starting side for Tuesday's contest.
Indeed, on-loan Manchester United midfielder Hannibal Mejbri is in line for a start, while Neil Etheridge, Lukas Jutkiewicz and George Friend are expected to be named in the starting XI for this game.
Forest Green Rovers possible starting lineup:
Doohan; Godwin-Malife, Casey, Cooper, Robson; Hendry, Peart-Harris, Stevenson; McAllister, March, Bakayoko
Birmingham City possible starting lineup:
Etheridge; Colin, Sanderson, Long, Trusty, Friend; Bacuna, Mejbri, Chong; Jutkiewicz, Hogan
We say: Forest Green Rovers 0-2 Birmingham City
Neither side will enter this match in the best of form, but we are struggling to look past Birmingham when it comes to this third-round contest. The Blues will have superior quality across the pitch, and we are expecting the Championship outfit to progress to the next round of the competition.