A century to Black Caps returnee Neil Broom and middle-order Bangladeshi collapse have given the Kiwis a 67-run ODI victory in Nelson.
Broom, who made his first international appearance in six years on Boxing Day, notched a clinical 109 not out from 107 balls as batting partners fell around him.
Set a target of 252, the Tigers were cruising at 2-105 before losing their last eight wickets for just 79 runs.
The win wraps up the three-match ODI series for the Black Caps, who will remain in Nelson for the dead-rubber game on Saturday.
Beyond Broom's century and some handy bowling from skipper Kane Williamson, the Kiwis had little to cheer about, struggling to dominate the contest.
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"There were a few learning curves for both teams today," Williamson said.
Losing the toss and batting first, the Kiwis lost Williamson (14) and opener Martin Guptill (0) cheaply, while Tom Latham could only manage 22.
Broom and partner Jimmy Neesham pulled the side back into the contest with a 51-run stand before Neesham was stumped for 28, before another handy partnership of 64 with veteran wicketkeeper Luke Ronchi.
The 33-year-old Broom brought up his maiden ton in the 48th over.
Bangladesh got off to a decent start in their run chase, but the match turned at 2-105 when Sabbir Rahman was run out for 38.
From there, the collapse was on, with Bangladeshi batsman from No.4 to No.7 reaching double figures.
A brief rally from keeper Nurul Hasan and skipper Mashrafe Mortaza gave the Tigers the smallest glimpse of victory, before Trent Boult snared them both.
