Louis Quilico was born in Montréal, Canada on January 14, 1925 to an Italian-born father and French-Canadian mother. He spent his formative years in the city, where his father owned a popular bicycle shop on rue St.-Denis.

During high school, he won a prize to study with Teresa Pediconi and the famous baritone Riccardo Stracciari at the Conservatoire Santa Cecilia in Rome, Italy. After returning home, he continued his studies with Martial Singher at the Conservatoire de Montréal and at Mannes College of Music.

In 1953, Quilico won first prize in the radio competition, Nos Futures Etoiles. Two years later, he won yet another competition: the prestigious "Auditions of the Air" sponsored by The Metropolitan Opera Company.