His debut album, Alive Till I'm Dead, was hugely successful, and earned the Londoner's bravado-laced wordplay a devoted following.
But last month's Read All About It, a link-up with Scots singer Emeli Sande, saw him top the single charts for the first time.
"I'm still not sure I am used to being famous," says Green, who plays the Barrowland on Monday.
"In the past few weeks it has changed enormously again, even from the first album, and now the parents of the kids who would stop me on the street and ask for a picture are now asking for a picture for themselves."
That success then continued with new album At Your Inconvenience, which reached No. 3 in the album charts.
While there is the usual mix of boasts and foul-mouthed humour that flung the 27-year-old to fame with his first record, Green reckons this album is a broader work, especially as it delves into serious issues, such as trying to cope with his father's suicide.
"It has put me in places I never went to on the first album," says the singer, whose real name is Stephen Manderson
"After all the touring to promote the first album, I think I found my voice in what I wanted to do with recording, and I found the confidence to really get my voice in there as part of it, from the artwork, to the album, to the videos, to what was chosen as singles.
"At the end of the first album we started getting more live instruments and strings, but I didn't really have the time to go as far as I wanted with it.
"Yet, looking back, I would not have changed anything on the first album.
"That was the ideal introduction and this is all about cementing the foundations."
Former Glasgow University student Emeli Sande has featured on both his albums.
"Emeli is incredible," he says. "She has an amazing voice and is an amazing person, so you can't even hate her for having all that talent.
"I think we work really well together, so it is a good relationship. I just think we get each other's vibe.
"There is quite a dark edge to what she does, which is similar to what I do."
He does not shy away from speaking out, either. After the riots in England this year, the singer was furious when a leading London journalist blamed rap music as the cause of the violence, writing that it created a "culture of hatred".
"I think the person who said it was the fault of rap music was an idiot," he says.
"He is meant to have had a better education than the people he is talking about.
"Surely if you are blaming anything for it then we have all got to take the blame because there is a generation lost that are rioting.
"It is about looking for reasons as to why people think it is acceptable to behave like that – I got loads of abuse from people claiming I was trying to justify it, which I wasn't.
"But, quite often, when you encourage people to think differently that is what you get."
He will get a great reaction in Glasgow on Monday night, however.
The gig, originally scheduled for October, is one the rapper is eagerly awaiting and he has also just announced a return date to the city at the O2 Academy next April.
"Scottish crowds are rowdy, in a non-violent way," he says.
"It's an aggressive appreciation, I thought I was going to get beaten up the first time I was there because I got put in a headlock by someone, who then told me how much he loved me, while speaking very fast.
"I was starting to panic, but he was just telling me how he had loved the show."
Despite his chart success this year, he is already planning ahead for his third album.
"I've started writing already, and have recorded a few ideas,.
"I just want to get back in the studio and try it. I don't have any set concepts for my albums, because I like to have shade, and just make the music I like to make."
l Professor Green, Barrowland, Monday, 7pm, sold out. Tickets for O2 Academy, £18.50, on April 23 go on sale tomorrow at 9am through www.gigsinscotland.com or 08444 999990.