Mattia Guadagnini was born in Bassano del Grappa, Italy, on April 11, 2002.

Guadagnini started racing in minicross when he was 8 years old and in 2019 he became world junior and European Champion in the 125 class. In 2021 Mattia debuted in MX2, winning three races and finishing the championship in fourth position.

In 2022 the move to MXGP and in 2023 the first podium, achieved in the Spanish GP (2nd overall).

In 2025 Mattia made his debut on the Ducati Desmo450 MX with a sixth place in Mantua in the first race of the Internazionali d'Italia.