The 24-year-old, who went on loan to Rotherham this term after injury, has played eight times since his return.
"We've got a (12-month) option on him (in the summer) and clearly I'm going to take that up," said McCarthy.
"We are in negotiations with him about a new contract. Whether he's happy with what we've offered him I don't know - Marcus (Evans) is dealing with it."
Hyam, who has made 105 league appearances for Ipswich, played in Tuesday's 2-1 victory over Reading which lifted Town into the Championship play-offs, with Brett Pitman's 89th-minute winner securing the Portman Road win.
"We worked unbelievably hard and scrapped and fought for everything," McCarthy told BBC Radio Suffolk of his side's performance.
"That was one of our hardest games all season, physically. We didn't play particularly well but we were playing against a really good team full of quality Championship players.
"All the things I talk about, resilience, determination and endurance, that is sometimes much maligned because people and I want sexy football - but it's not always a league you can do it in.
"As I've found over my 24 years doing it, you tend to get more out of it with all those physical, tough qualities than you do with just wanting to be a nice football team."
Ipswich are in talks with midfielder Luke Hyam over a new contract, according to boss Mick McCarthy.