Golam Rabbani Chhoton’s team beat Nepal 2-1 at the Chalnglimithang Stadium in Thimphu, Bhutan on Tuesday.
They top the group with 6 points from two victories in as many matches, including a 17-0 rout of Pakistan.
Bangladesh will now face Group A runners-up and hosts Bhutan on Friday in the battle for a place in the final.
India and Nepal will clash in the other semifinal the same day.
Bangladesh kept putting pressure on Nepal, who beat Pakistan 12-0 in their previous match, right from the start.
Sirat Jahan Shopna, who alone had put seven past Pakistan, gave Bangladesh the lead in the 16th minute by beating a defender, who was shadowing her, for pace.
Krishna Rani Sarker extended the lead after another 16 minutes when she was fed a long ball by goalkeeper Rupna Chakma.
Rashmi Kumari Ghising’s goal in the added time of the second half brought some solace to Nepal.