Born in Maranello, Modena, Montagnani graduated as a teacher.

Starting in 1918 she worked as a governess and a gardener in many noble houses in France and Italy.

[1] At 68 years old, while working at the Palazzo Barberini as a gardener, she was discovered by Federico Fellini who gave her supporting roles in Giulietta degli spiriti, Satyricon and The Clowns.

[1][2] From then, for about 25 years, Montagnani appeared in dozens of films and stage works.

[1][2] She obtained a large popularity with the role of Natalina, Nino Manfredi's chambermaid in a long series of Lavazza commercials shot between 1979 and 1990.