Chief Whip Nurul Islam Moni has said Article 70 of the Constitution will apply to the presidential election as well.
Citing the article, he said on Tuesday that MPs cannot vote against their party's decision, and any one who does so will lose their parliamentary seat.
The presidential election will be held in parliament's session chamber on Aug 20.
A total of 349 lawmakers, including 50 women from reserved seats, are eligible to vote.
Ruling BNP and the 11-party alliance have both announced candidates for the election, ruling out the usual unopposed win for a single candidate.
MPs will openly write their name in front of their chosen candidate along with a serial number, meaning their vote will be identifiable, the chief whip said at a media briefing after a preparatory meeting in parliament.
No special session will be called for the election, he added.
The chief election commissioner will convene the sitting on voting day, with MPs seated at their designated seats and the commissioner presiding as election authority.�"bdnews24