New Democracy's Sofia Voultepsi quit as deputy Health Minister late on Monday citing “personal reasons.”
She was replaced by Zetta Makri, also from the conservative party.
Reports Tuesday said Voultepsi's decision was linked to the appointment of Adonis Georgiadis, a former member of the nationalist LAOS party, as Health Minister.
Greek Prime Minister Antonis Samaras on Monday revamped his cabinet after losing one of two coalition partners, giving PASOK key ministries in a bid to consolidate support from his remaining partner.
The new cabinet will be sworn-in at 12.30 Tuesday.