The 31-year-old forward bolsters Ross Jenkins' attack and goes straight into the Hoops' squad to face Chelmsford City this evening.
An Antigua and Barbuda international, Parker began his career with Queen's Park Rangers and brings EFL experience and pedigree with spells at Oldham Athletic, Oxford United, Gillingham and Charlton Athletic, as well as spells abroad for Slovenian side Domzale and Red Star Belgrade in Serbia.
His spell at Priestfield saw him net 16 goals in 79 league games, prior to his move to Charlton Athletic. Parker, a former schoolboy at Wycombe, was re-signed by Gareth Ainsworth in 2019 and made 18 appearances as Wanderers reached the Championship via the play-offs.
After signing with City, Parker said: "It's very exciting and I'm very happy to sign.
"I've had a tough year out of football after an injury, so it's nice to get back into football and nice to sign for a club that is very close knit, well run and a group of player who have ambition."
Welcome to the club Josh!