Blues' regional high performance manager Gafyn Cooper said, "It was another highly competitive game during which both sides enjoyed spells when they were on top.
"The South started well and looked capable of winning for the first time this season. However, the North produced a second outstanding performance of thye campaign and in the end ran out comfortable winners."
No.8 Garrick Legge, prop Richard Powell, wing Will Rose and full back Sean Nicholas raced in for tries whilst Nicholas added two conversions to round off an excellent night's work.
Meanwhile at Stradey Park the Ospreys missed out on a second successive victory of the season - going down 18-10 to the Scarlets.
Having beaten the Dragons in their opening game, the Ospreys might have fancied their chances of picking up a victory at the expense of the Scarlets who lost out to Blues North at Pontypridd on the opening night.
However, the Scarlets were the better team on the night and ran in tries through Josh Smart and Rhys Gingell with outside half Jonathan Thomas adding a penalty and a conversion.
The Ospreys hit back with a try from no.8 Scott Hicks, but a conversion from Craig Davies and a penalty from full back Chad Punchard were not enough to prevent the Scarlets from a gaining the victory spoils.