A youth academy graduate of Spezia, Mulattieri made his professional debut on 14 April 2018 in a 1–1 draw against Frosinone.[2] He scored his first goal following week in a 3–2 defeat against Pescara.[3]
On 5 October 2020, he joined Dutch club Volendam on a season long loan deal.[7] On 27 July 2021, he joined Serie B club Crotone on a season long loan deal.[8] On 25 July 2022, he moved to Frosinone on loan, with an option to buy.[9]
Sassuolo
On 7 July 2023, Mulattieri joined Sassuolo on a permanent transfer.[10]
International career
On 7 September 2021 he made his debut with the Italy U21 squad, playing as a substitute in the qualifying match won 1–0 against Montenegro.