Born in Florence, Italy, began working in a bycicle shop, learning the basics of applied mechanics; later, he went to work in a car garage, where developed a strong love for engines and cars.
Poor economic condition forced him to work as a bus driver for local services.
In 1923 Materassi, with the help of some wealthy friends, opened his own workshop in Via dei Poggi 12, in Florence: he called it "L’Autogarage Nazionale", and signed a contract of representance with the Turin automaker Itala
Itala was a builder of aeronautical engine, toghether with Hispano-Suiza: after World War I the company had a surplus of spare engines, and Materassi succeeded in buying one of those at a very low price. Materassi heavily modified the engine, and built a car around it, calling his- first racecar "Italona".
The car was quite heavy, with over 2 tons of mass: nevertheless, the 3 liters aviation engine was powerful enough to allow good performances even in hill climbing races. With the Italona, Materassi wins twice the Montenero Race, earning the nickname of "King of Montenero”. In later years, he gained other two victories on this difficult race, one with Bugatti, and one with Talbot.
From 1923 to 1927 Materassi won lot of important, but local, races, including the Grand Prix of Rome in 1925 and four "Cups of Pistoian Hills": he manages to het a fourth place in the prestigious Targa Florio.
Impressed by the skills of the young pilot the team manager of the Bugatti asked Materassi to join his racing team. In his first race with the brand new Bugatti T35C , he won the Tripoli Grand Prix, with a mean speed of 132 km/h, and later finally won the Targa Florio.
Those victories, along with others, gain him the title of "Absolute Champion of Italy".
In 1928 Materassi founded his own racing team, buying cars and material from the bankrupt Talbot team. Materassi worked himself on the engines and the frameorks, modifying the old cars to make them 30 kilograms lighter.
In June 1928 he won the Grand Prix of Mugello driving a Talbot and finished second in the Coppa Acerbo in August then that same month he won his fourth Coppa Ciano at the Circuito del Montenero, beating both Tazio Nuvolari and Giuseppe Campari.
At the 1928 Italian Grand Prix held at the Autodromo Nazionale Monza, Materassi lost control on the 17th lap and was killed instantly when the car crashed into a grandstand. Twenty-seven spectators (but some newspapers accounted only 20) were also killed and a large number injured.