Prop Toka Natua scored a hat trick, including tries either side of halftime, as her team upstaged the defending champions 41-32.
After winning four straight World Cups, beating England in three finals, the Black Ferns failed to make the semifinals in 2014 and watched England triumph in Paris.
But in benign conditions in Belfast, the New Zealanders came from 14 points down in a grinding first half to win comfortably in the end by nine.
It was only after they scored their seventh and last try, a second by fullback Selica Winiata from a cross-kick by flyhalf Victoria Subritzky-Nafatali, in the 69th minute that the Black Ferns made certain of their record-extending fifth title.
New Zealand 41 (Toka Natua 3, Selica Winiata 2, Charmaine Smith, Kendra Cocksedge tries; Cocksedge 3 conversions), England 32 (Lydia Thompson 2, Isabelle Noel-Smith tries; penalty try; Emily Scarratt 2 conversions, 2 penalties). HT: 10-17
