The 27-year-old is currently with Greek outfit Panathinaikos but due to financial problems, they are happy for him to move on.
Quincy has spent the last week with Palace and he has impressed in pre-season games against Dagenham and Gillingham.
The former Arsenal man is now set for talks over a deal and his agent Leon Callander confirmed to Sky Sports that a deal was in the offing.
"He has been really impressed with everything about Palace and with the manager too," he said.
"He is hopeful that a deal can be done."
Palace boss Ian Holloway confirmed that he was taking a serious look at Quincy and was considering whether to offer him a deal.
"It's whether he works with the group and with me," he told the Croydon Advertiser.
"I've got to try and get him up to speed, and the speed after those runs he makes take a while to recover.
"I do like him. What I was told about him as a person isn't true - there were lots of rumours - but he's playing with a smile on his face and my job is to get him a contract."