New Zealand salvaged a remarkable 17-run victory over Bangladesh Saturday to set up a crunch clash against defending champions Australia for a place in the women's T20 World Cup semi-finals.

Coming off a narrow loss to India, the White Ferns won the toss and opted to bat on a slow Junction Oval pitch in Melbourne.

But after reaching 66 for two they collapsed to 91 all out, as Ritu Moni grabbed a tournament-best 4-18 with back-up from fine fielding.

A first World Cup victory for Bangladesh since 2014 was within reach, but they blew the chance with sloppy batting and poor running between the wicket seeing them bundled out for 74.

"Obviously nowhere near what we wanted to post today, but Bangladesh were fantastic, they put us under pressure on a really difficult wicket," said New Zealand captain Sophie Devine.

"We learned from what Bangladesh did, bowling straight and making the batters make mistakes and then we know what our spinners can do."

India are already qualified for the last four from Group A with New Zealand and Australia both on two wins from three, effectively making their Monday clash in Melbourne a quarter-final.

Bangladesh are eliminated after losing three from three while Sri Lanka, who play India later Saturday, will be out of contention even if they win their last two matches.

Good line and length from Bangladesh's bowlers restricted openers Devine and Rachel Priest to just 23 from the first five overs.

The runs started flowing but Devine fell to spinner Salma Khatun on 12 while trying to force the pace. Priest soon followed, lbw for 25, to leave them under pressure at 40 for two in the ninth over.

Experienced campaigner Suzie Bates' departure for 15 sparked a collapse, with the rest of the wickets falling for just 25 runs.

Bangladesh began the chase well, moving to 17 without loss before Kasperek snared Murshida Khatun for 11 then Hayley Jensen removed Ayasha Rhaman, leaving them on 19 for two.

Miscommunication saw Faranga Hoque run out without scoring just three balls after replacing Nigar Sultana Joty, who left the field clutching her jaw after being hit on the helmet. They began unravelling with Moni run out soon afterwards.

By the 15th over they were 51 for six, still needing 41 to win, and sensing a famous comeback New Zealand kept their cool to keep their tournament alive with Jensen snaring 3-11.

"Our bowling and fielding was good but the batting wasn't up to the mark," admitted Bangladesh skipper Khatun. "One match left, next match we need to improve our batting."