Victory over the USA a day earlier had put Kathryn Bryce's side joint-top of the four-team table, where the first and second-placed sides will progress into a semi-final qualifying match for next year's tournament in South Africa.
A poor batting display proved costly for Scotland, who were dismissed for 77 and have now seen Bangladesh move clear at the summit ahead of the final round of group fixtures on Wednesday.
Bryce's decision to bat first backfired after they lost a raft of early wickets, with Lorna Jack the lone fighting figure.
Jack's 22, which included three boundaries, helped set 78 for victory but it was achieved with seven overs to spare by Bangladesh.
Rachel Slater claimed two for 13 but Nigar Sultana's 34 handed out a heavy defeat to Scotland, who need to beat Ireland to keep alive their World Cup hopes.
Elsewhere, Ireland bounced back from defeat against Bangladesh to claim an emphatic T20 World Cup qualifying victory over the USA in Abu Dhabi.
After dismissing their opponents for 91, Ireland's opening batters Amy Hunter and Gaby Lewis underpinned a nine-wicket victory with 6.5 overs to spare.
Hunter was dismissed for 43, but Lewis remained unbeaten on 44 as Ireland cruised home.
Earlier, the USA collapsed from 52 for one, with four run-outs in their innings.
Captain Sindhu Sriharsha top-scored with 25 before she was bowled by Laura Delany, who conceded just six runs from her four overs, while Eimear Richardson took two for 19.
Two of the eight teams in the competition will advance to the World Cup in South Africa next year.
Bangladesh remain top of Group A, with Ireland's next game being against Scotland on Wednesday.