Born in Uberaba, Minas Gerais, Arnaldo moved to São Paulo at early age, after being spotted by a former player, Jorge Lima; he joined a youth setup in Bady Bassitt in 2010 before moving to Mirassol's youth squads in the summer.
[1] On 17 April 2011 Arnaldo made his first-team debut, coming on as a second-half substitute of a 0–3 loss at Botafogo-SP, for the Paulistão championship.
[4] He returned to Mirassol at the end of the year, and after impressing while on the club in 2014, he joined Portuguesa on 23 April 2014.
[5] On 3 December, after appearing regularly for Lusa, Arnaldo moved to Penapolense, also in a temporary deal until May.
[7] On 10 January 2019, Arnaldo was loaned out to Ponte Preta for the 2019 season from Botafogo.