The League One fixture at Portsmouth on Saturday 9 October has been postponed due to international call ups involving the Pompey squad.
A new date for the game will now be found and when agreed the club will make supporters aware of when the team will be travelling down to Fratton Park.
Cheltenham haven't played away at Pompey since May 2017, and this season the two clubs are set to meet for the first time at League One level.
In October, the Robins face Rotherham United, Exeter City in the Papa John's Trophy, Accrington Stanley, Morecambe, Chelsea under-21s in the Papa John's Trophy and Sheffield Wednesday all in home fixtures with one away game scheduled at Doncaster Rovers.