The Foxes are enjoying a remarkable season, as they fight for a top four spot in the Premier League and face off against Chelsea in the cup final at Wembley.
Maddison was back in the side after missing their loss to West Ham United in the Premier League last weekend, due to breaching COVID-19 protocols.
"We are in the FA Cup final," Maddison tweeted.
"Wow...I never thought I'd be able to say that as a young boy. Great to be back out there representing my club.
"A lot of hard work and making up to do from now until the end of the season with so much to play for. Let's go!"