Manchester United's defender is hoping to make his senior Northern Ireland debut against Romania in the Euro 2016 qualifiers.
The Northern Ireland international came on as a sub after Chris Smalling was sent off in the Manchester derby on Sunday.
With Phil Jones, Johnny Evans and Marcos Rojo all side-lined due to injuries and Chris Smalling suspended, the 19-year-old defender is in line to start for United against Crystal Palace on Saturday.
Mcnair, who made his senior debut for United on the 27th of September against West Ham United in a 2–1 victory at Old Trafford told ManUtd.com: "It's really good," when asked about the call-up. "When I was growing up, I always aimed to play for my country. Obviously, as I've been playing for United, one of the biggest clubs in the world, I did hope I would receive the call.
"I'm really happy to get called up. I could have been involved last month for the Faroe Islands and Greece games, so it's great I've been recalled to join the squad for Romania."
McNair is very eager to continue his good progress at Old Trafford and looks forward to going to Bucharest with his international team-mates.
"I want to keep working hard and try to play as many games as I can for United," he said. "Hopefully, I can break into the Northern Ireland team when I go. I do know a few of the lads - Corry Evans and Luke McCullough from United, of course. I know some others from the Under-21s, so I am looking forward to it."
Northern Ireland are top of Group F with three wins out of three games and play Romania - who are in second-place - on the 14th of November.