Taking out six Tui awards, 21-year-old Lorde undoubtedly ruled the night with wins including best album, best single and the publicly voted People's Choice Award.
Ardern, who attended the awards with partner Clarke Gayford, took to the stage to present the People's Choice Award.
Lorde seemed genuinely stunned to have Ardern on stage with her.
"Oh man, Jacinda Ardern is up here guys."
She pulled Ardern towards her in a one armed embrace, saying "come over here".
"I can't believe you're at the New Zealand Music Awards, this is like a big deal for music."
Ardern returned the sentiment.
"Presenting to you is a big deal - mutual fan girl."
Lorde thanked her and said "it means so much" before leaving the stage with her haul.
Ardern jumped on Instagram to document the night, posting a picture of musician Teeks, who took out Best Maori Artist.
Lorde began the night on a high, winning the first award of the evening for best solo artist, before returning to the stage to collect best pop artist.
She also claimed the International Achievement Award for the fourth time, before taking to the stage for a stunning live performance of her hit single Green Light.
Her total six awards brought her lifetime haul of New Zealand Music Awards to 18.
Accepting the award for Album of the Year, the Kiwi star brought her brother on stage to celebrate.
