Playing in Wellington, Otago made a terrible start with the hosts up 14-0 after seven minutes.
Otago came back into the game but never got near enough to challenge as Wellington ran out the winners, and grabbing a bonus point with the victory.
Otago's best were backs Vilimoni Koroi and Sio Tomkinson, while Slade McDowall and Aki Seiuli went well up front.