The 23-year-old, who came through the Norwich City academy, is the Saddlers’ fourth signing of the January window.
He joined Oxford last summer from Southern Premier League side King’s Lynn, and has since made 12 appearances for the Us.
He is expected to be eligible for tomorrow's clash with Gillingham.
“I’m absolutely buzzing,” said Norman. “I’m predominantly a right-back but I love to get forward just as much as I love defending. You can expect to see me flying down the right-hand side.
“The manager has told me to play freely and make sure I know my roles and responsibilities.
“I want to contribute to the team, whether that is going forward and getting crosses in or defending and keeping those all-important clean sheets.
“I’m a defender first and foremost so a clean sheet is something I will be striving for.
“I want to be successful with Walsall and bring success to both the club and myself, which will hopefully come hand in hand.”
Walsall boss Dean Keates said: “We’re over the moon to add Cameron to the squad. He’s joining us on a long-term contract and is someone we see as being a useful addition to the club going forward.
“He’s a big, strong right-back who defends the back post well and gets forward.
“He’s at the right age for us to work with him and he’ll add competition to the players that are already here.”
Norman has also played for Woking, Concord Rangers, and Needham Market.