He played friendly games only for A.C. Milan from 1909 to 1911.[3]
He was an elite referee from 1911 to 1917.[3] On 7 June 1925, he served as a referee in one of the finals between Genoa and Bologna of the 1924–25 Prima Divisione (Northern League).[2]
He was President of the Italian Referees Association from 1920 to 1927.[2]
The Premio Giovanni Mauro ("Giovanni Mauro Award") – one of the most prestigious awards given to the referee considered to have performed the best during each Serie A season – is dedicated to his name.[2] In 2011, he was inducted into the Italian Football Hall of Fame.[6]