The actor – who plays the role of Spanish teacher Will Schuester in the musical TV show – admits he is excited to see where the series will go at the end of the third season as many of the stars, including Lea Michele, will be graduating and leaving.
He said: "What to expect? I don't know if I can give away too much, but there will be a lot of people graduating at the end of the season.
"I'm not sure what that's going to mean for the show, we're probably going to get a lot of new members and maybe some of the old 'Glee' members will become student teachers of mine, I don't know."
Matthew also thinks many people will have been "surprised" when they saw his character Will finally in a relationship with germ-phobic teacher Emma.
He said in a video for internet search engine site Bing: "It's my favourite season so far. I think the coolest thing is that for Will's character is he's in a great relationship with Emma, you know the first episode you see him rolling over in his bed and she's there living with him now. I think that was a big surprise for people."