Centre-back Morrison, 22, has signed a new deal which keeps him at the Championship club until the summer of 2017 having made 37 appearances since arriving from Swindon in January 2011.
"It's wicked," said Morrison, currently recovering from a knee injury. "We've been talking about it now since the end of last season and it feels great to finally get it done and now I can concentrate on getting fit and getting back in the team.
"Captaining the side this year has probably been my greatest achievement in football and I want to be back out there as soon as possible."
Midfielder Obita has also put pen to paper on a new three-and-a-half-year deal with the Royals.
The 20-year-old academy graduate has made his first-team breakthrough under manager Nigel Adkins this season following loan spells with Barnet, Gillingham, Portsmouth and Oldham.
Obita added on the club's official website: "It feels great to sign another contract at Reading. It's a club I've been at since I was eight years old, 11 years in total now, going through the ranks and now playing in the first team.
"So much has changed since I signed my first professional deal here, so to sign again is a fantastic feeling."
Meanwhile, second-year scholars Aaron Kuhl and Jack Stacey have both signed professional contracts with Reading until 2016.
Central midfielder Kuhl and fellow 17-year-old Stacey, who can play in midfield or at full-back, have both impressed throughout the Berkshire club's youth ranks.