Bangladesh pace bowlers dominated the opening session on a bouncy Darwin pitch, reducing Australia to 74 for four at lunch.
Hasan Mahmud provided the initial breakthroughs after a 45-run opening stand. He dismissed both Australian openers in quick succession, removing one caught behind for 23 and bowling Travis Head for 22.
Ebadot Hossain maintained the pressure from the other end. Despite a dropped catch in the slips off Steve Smith, Ebadot struck soon after by getting Marnus Labuschagne caught at slip for just one run.
Cameron Green attempted to counter-attack with a quickfire 13, including a six off Taskin Ahmed. However, Taskin outsmarted the batter on the final ball before lunch, forcing a miscue that was caught at short mid-wicket.
The early strikes leave Australia in trouble heading into the afternoon session.