The 25-year-old midfielder has signed a one-year deal with Ian Holloway's newly promoted Eagles after his contract with Championship side Blackpool expired earlier this summer
The 25-year-old midfielder, who played under Palace boss Ian Holloway at Blackpool, moves to Selhurst Park on a free transfer after being released by the Championship club earlier this summer.
"I’m very excited. I had a very good year in the Premier League with the gaffer, so I’m excited to start the new season," Grandin told the club's official website.
"We had a very good run [at Blackpool]. I think the team played well, but we were unlucky at the end because we went down. We had a very, very good year though, we enjoyed it and I hope it will be the same with Crystal Palace."
Grandin, who was handed a contract by Holloway after playing just 45 minutes as a trialist in Palace's pre-season fixture against Dagenham and Redbridge, is buoyed by the prospect of returning to the Premier League.
"It’s like a cup final every game. You play against great players, great teams, so you have to be focused on your football and everyone has to give their best because it’s a difficult league – the best league in the world, I think," he said.
"All the teams are very good. In the French league or in the Spanish league, you have six strong teams, but I think in the Premier League I think all the teams are very strong.
"Everybody can beat everybody, so it’s hard to say who will stay up, who will go down. If we work together and the team is confident, anything is possible."