BBC One controller Danny Cohen and comedy commissioning controller Cheryl Taylor green lit the second run following strong ratings for the Brendan O'Carroll sitcom.
Based on a stage show about Dublin matriarch Agnes Brown (O'Carroll), the show also featured O'Carroll's real life family members in the extended cast.
"This is unbelievable! I'm just thrilled that the BBC continues to have confidence in the show," said the comic. "The support we have had from all involved, from Danny Cohen and Mark Freeland and BBC Scotland, makes us just so excited to get back there and do it all again.
"Producer Stephen McCrum promised me that he would be faithful to the stage show and he has gone beyond this in making the show the success it is. I am living the dream."
Last week's episode of Mrs Brown's Boys picked up an impressive three million viewers in the 10.45pm slot.
Cohen commented: "Mrs Brown has been a big hit with BBC One viewers. It's a laugh-out-loud funny show with wonderful performances at its heart."
Taylor added: "Brendan O'Carroll and his irrepressible alter ego Agnes Brown have lit up Monday nights for the past few weeks and, despite the rarefied language, the warmth of this series and the laugh-out-loud comedy antics have proved a huge hit with BBC One viewers. We're delighted that Agnes and her wonderful family will be returning later in the year."