The 20-year-old has put pen to paper on a new deal that will see him remain with the club until the end of the 2015-16 campaign.
He broke into Nigel Pearson's first team in the Capital One Cup at the start of last season but then suffered a stress fracture to his leg, so was out for much of the campaign as Leicester were promoted to the Premier League.
"Last season started with a lot of promise for me, but unfortunately I got injured, which meant I didn't play as much as I could have," Hopper told the club website.
"I'm fully fit now and I can't wait to get started again in pre-season by showing what I can do."
Hopper spent most of the 2012-13 season on loan at Bury, scoring three goals in 24 appearances.