Mónica Haydée Fein (born 3 June 1957) is an Argentine biochemist and Socialist Party politician who was intendente (mayor) of Rosario from 2011 to 2019.

[3] Hermes Binner, a fellow Socialist elected mayor of the city, appointed Fein Secretary of Public Health in 1997.

She strengthened the local primary care network, focused efforts on hospital standards, and launched the Center for Ambulatory Medical Specialties of Rosario (CEMAR).

She headed the party list of Socialist candidates to the City Council in 2001, and remained in the post until 2003, serving as President of the Health Commission.

She was named Secretary of the Commission for Social Action and Public Health, and also served in the Committees on Rules, Taxes, Constitutional Affairs, General Legislation, Population and Human Development, and the Elderly.