The Torchwood star will join Jackie Bird as presenter of this year's show at Glasgow's SECC on 19 November.
Last year Â£39m was raised to help improve the lives of disadvantaged children.
Anyone who would like to be in the audience can register now for free tickets at bbc.co.uk/tickets.
Other acts confirmed for the evening are dance group Punjabi No 1 and The Box, music acts Pearl and the Puppets, Clanadonia and The Gospel Truth Choir as well as comedians Fred MacAulay, Craig Hill and Des Clarke.
Further performers are due to be announced in the coming weeks.
Northern Ireland and Wales are also staging their own concerts, with highlights of all regions shown to the whole of the UK during the national TV appeal.
John Barrowman said: "Working on Children in Need is always a highlight of my year.
"The cause is such a worthy one, and unfortunately right now the number of children in need in the UK is growing.
"I'm really looking forward to doing what I can to raise spirits and lots of cash."
BBC Radio Scotland will also have full coverage of the event, culminating in a special programme hosted by Bryan Burnett and Radio One's Edith Bowman.
John Barrowman and the cast of the hit musical We Will Rock You have confirmed they will join Pudsey for Children in Need Scotland next month.