The appointment of Imam, a former first-class cricketer, comes after New Zealand's Mark Coles resigned as head coach of the women's team recently.
The PCB also confirmed that the national women's team will take on England in Kaula Lumpur before the ICC event. The Pakistani eves will play England in the seventh round of ICC Women's Championship, where the two teams will compete in three ODIs and as many T20Is.
Bismah, the 28-year-old veteran of 105 ODIs and 103 T20Is, was first appointed as Pakistan captain in the T20 format in 2016 for the tour of England before taking over as ODI captain post ICC Women's World Cup in 2017. Till date, she has led Pakistan in 15 ODIs and 33 T20Is.
Maroof said it was an honour to lead Pakistan again in a World Cup.
“The team is in good shape and has produced some good performances recently. There is a great deal of talent and passion in the girls and I look forward to carrying the momentum to the World Cup,” she said.
Chief selector and former captain Urooj Mumtaz said Pakistan have a good chance of doing well in the ICC event.
“There has been a significant improvement in the performances of the women's side of late and her (Maroof's) vast experience of international cricket is certainly going to benefit the team,” Mumtaz said.
The Pakistan women's team recently beat Bangladesh at home and have also done well against other opponents including against South Africa early this year.
The ICC Women's T20 World Cup will be held in Australia from February 21 to March 8.