McClennan, 49, will take over from Ivan Cleary at the end of the season on a two year deal.
Warriors chief executive Wayne Scurrah said: “It’s fantastic for us as a club, for our members and all fans that we’ve been able to appoint Brian as our new coach.
“There was interest in the position from inside the club and from coaches overseas including some in the United Kingdom.
“Brian came through as the most suitable candidate. He has had outstanding results with every team he has been involved with, be it the Kiwis, the Leeds Rhinos or club teams in Auckland and we’re delighted one of the best coaches in New Zealand rugby league history is to be the next coach of the Vodafone Warriors.”
He said: “I’m so excited and honoured to have this opportunity.
“I’ve been fortunate enough to coach the Kiwis, Leeds and Auckland club sides but my ambition always was to one day coach in the NRL, the toughest competition there is. To have that chance from next year is brilliant and to be able to achieve it with the Vodafone Warriors in my home town couldn’t be better.”