The blue and golds ran out 54-36 winners, after leading 27-12 at the break, scoring eight tries to six to pick up its fourth straight win.
Defence rather went out the window from both teams - especially in the later stages of the match - and tries came from every part of the field.
But Otago was always in the ascendancy and had the win in the bag early in the second half when it was up 42-12.
Northland threw everything but the kitchen sink at Otago in the final 20 minutes and scored four tries in the final 18 minutes as it picked up its first bonus point of the competition.
Otago rather went to sleep in the final stages of the match but did not have to worry such was its lead.
Otago has certainly been on a fine attacking mindset of late. It is scoring tries at will and in its last four games it has scored a total of 191 points, bagging 24 tries on the way.
The win has cemented third position on the ladder for Otago with one game to go against Bay of Plenty at Forsyth Barr Stadium on Sunday.
It will play either Hawkes Bay or Wellington in a semifinal on October 17.
Otago could have actually nudged past 60 last night but its kickers missed half of their shots though many of them were from the sideline.
The side continued to look polished and threatening in attack and no-one was more dangerous with the ball in hand than fullback Tony Ensor.
Given more freedom to roam than a merino missed in the muster out the back of Maniototo, Ensor chewed up the metres and was too quick for the Northland defence.
He had a direct hand in Otago's first three tries, scoring one himself and Northland wisely decided in the second half to not kick the ball to the Otago fullback.
Jayden Spence showed some nice touches on the wing while first five-eighth Fletcher Smith was lively when he decided to run.
The Otago forward pack was on top throughout the match and its lineout, especially big lock Josh Dickson, who won plenty of ball, while flanker James Lentjes showed his class.
Otago had all the ball and territory in the opening half and Smith banged a penalty over after eight minutes.
Otago got reward for its clear dominance with its first try after quarter of an hour.
Fullback Ensor received the ball 40m out from the Northland line and weaved his way through the home side's jagged defence.
He linked with centre Michael Collins, who jogged over to score the try.
Five minutes later and Ensor was at it again.
He blew off a couple of Northland defenders and after a series of passes, the Otago players were queueing up to score and Smith went over.
Northland was looking a poor second but it finally got some ball and lock Shane Neville barged over under the posts.
Ensor though was not finished. He ran on to the ball from a well timed Collins pass and simply burned off the Northland defence to score just before the half hour.
Lentjes scored the bonus point try for Otago five minutes from halftime from a rolling maul off a lineout.
