The 25-year-old has been trialling with Boro throughout July and his goals and impressive performances have earned him a deal ahead of the brand new Vanarama National League South season.
Back for his second spell in Hampshire, Connor initially joined Farnborough from Chertsey Town at the start of the 2018/19 season.
Cullen found the net 10 times during his first season with The Yellows and improved his total the following season with 13 goals back in the 2019/20 campaign.
The Chertsey born striker started his playing career with Brentford, before switching to Staines Town, Sandgate and then Uxbridge.
Upon signing on the dotted line, Connor beamed:
“I’m buzzing to be back!
“I love the staff, the fans and the club and can’t wait for the season to start now.”
Manager Spencer Day added:
“Connor is obviously known to us but has been a massive positive this Pre-Season and has earned a contract.
“He’s been a threat every time he’s been on the pitch and I know will give us everything.”
View the updated Squad list.