Born in Rome, Gerini entered seven Formula One World Championship Grands Prix, making his debut on 22 January 1956. Over his brief Formula One career, he scored a total of 1.5 championship points, a result influenced by shared drives, which were permitted under the regulations of the time.
In addition to his World Championship appearances, Gerini was an active driver in numerous non-championship Formula One races. He also competed extensively in sports car racing, driving for prestigious marques such as Ferrari and Maserati.