In the motorcycle world championship he made his debut in 1973, when he instituted a DRS with no greater success in the class up to 125 cc. In the second half of the season, he joined the class up to 250 cc and was able to win with a Yamaha privately entered two fourth places.
The following year, Paolo Pileri has been committed for the Morbidelli factory team and moved back to the eighth liter class, where he in 1975 with seven wins at the Grand Prix of Spain, Austria, Germany, the Grand Prix of Nations at Imola and the races in Holland, Belgium and in Sweden superior world champion was ahead of his teammate Pier Paolo Bianchi.
After the third place in the World Cup of 1976 ( behind world champion Bianchi and the star of the small displacement classes at this time, the Spaniard Ángel Nieto ) moved Pileri 1977 together with the Morbidelli team again in the class up to 250 cc, but the team had to fight in the larger class of initial difficulties. At the Grand Prix of Austria 1977 Pileri was involved in the 350cc race in a mass accident and was sidelined due to injury as a result. His replacement at Morbidelli, compatriot Mario Lega, then won the 250cc world title. In 1978 he celebrated in the quarter-liter class at the Grand Prix of Belgium its eighth and final Grand Prix victory. 1979 ended the Italians his driving career.
Mid-eighties, Paolo Pileri was active as a team manager in motorcycle racing again. With his protégé Loris Capirossi he could win the 1990 and 1991 World Cup in the eighth liter class in 1992 his driver Fausto Gresini was in the same class runner-up.
Pileri died on 13 February 2007 of a heart attack.