Tamim Iqbal and Shakib Al Hasan maintained their fine form as Bangladesh eased to a 91-run victory which leaves Zimbabwe facing a tri-nation series exit.
The Tigers, already guaranteed a place in the final on Saturday, exploited Zimbabwe's batting frailties in Dhaka on Tuesday, bowling them out for only 125 in reply to 216-9.
Tamim made his third successive half century on a tricky surface, top scoring with 76 and putting on 106 for the second wicket with Shakib (51) but Graeme Cremer (4-32) and Kyle Jarvis (3-42) did the damage as the hosts collapsed to 170-8.
Sunzamul Islam and Mustafizur Rahman took Bangladeseh over 200 and Zimbabwe, really needing a win in their final round-robin match to deny Sri Lanka a place in the final, never looked like chasing down their victory target.
Shakib (3-34) took his tally of wickets in the tournament to nine after making a second half-century, while Mashrafe Mortaza, Sunzamul and Mustafizur took two wickets apiece as Zimbabwe's shortcomings were exposed.
Sikandar Raza made 39 and Cremer 23 after reaching the 100 ODI wicket mark, but Bangladesh eased to a bonus-point victory to maintain their 100 per cent record and Zimbabwe drop below Sri Lanka on net run-rate.
Sri Lanka and Bangladesh meet in the last round-robin match on Thursday.