Richard Langley is training with the Palace squad in a bid to earn a full-time contract with the club.
The Cardiff midfielder has been told he can leave Ninian Park as the Bluebirds look to trim their wage bill further.
Cardiff manager Dave Jones is happy to let the 25-year-old go, and would ask only a nominal fee for a player who cost £200,000 from QPR two years ago.
The Jamaican international has been training with the Eagles players for the last few days and is keen to earn a deal at Selhurst Park.
"I'm there for a few days and we'll see what happens," he said. "Palace would be a good club for me to play for."