Firmino said that it was his "dream" to play in the national team though he had no "contact with national team manager Dunga".
On 23 October 2014, Firmino received his first call up to Brazil national football team for the friendly matches against Turkey and Austria.
He commented, "I'm very happy about the nomination and would especially like to thank the team".
He debuted in a 4–0 win over Turkey on 12 November, replacing fellow debutant Luiz Adriano for the last 17 minutes.
Firmino scored his first goal  six days later in the latter match, a 2–1 away win.

In May 2015, Firmino was included in Brazil's 23-man squad for the 2015 Copa América to be held in Chile.
On 21 June, he scored in a 2–1 defeat of Venezuela to qualify the Seleção for the knockout stage as Group C winners.

In May 2018 he was named in Tite's final 23 man squad for the 2018 World Cup in Russia.
On 2 July, Firmino scored Brazil's second goal in a 2–0 win over Mexico in the round of sixteen having come on as a late substitute.

In May 2019, Firmino was included in Brazil's 23-man squad for the 2019 Copa América.
Firmino played all 90 minutes of the final as Brazil won 3–1 to lift their ninth Copa América title.
Firmino said that it was his "dream" to play in the national team though he had no "contact with national team manager Dunga". On 23 October 2014, Firmino received his first call up to Brazil national football team for the friendly matches against Turkey and Austria. He commented, "I'm very happy about the nomination and would especially like to thank the team". He debuted in a 4–0 win over Turkey on 12 November, replacing fellow debutant Luiz Adriano for the last 17 minutes. Firmino scored his first goal  six days later in the latter match, a 2–1 away win.
In May 2015, Firmino was included in Brazil's 23-man squad for the 2015 Copa América to be held in Chile. On 21 June, he scored in a 2–1 defeat of Venezuela to qualify the Seleção for the knockout stage as Group C winners.
In May 2018 he was named in Tite's final 23 man squad for the 2018 World Cup in Russia. On 2 July, Firmino scored Brazil's second goal in a 2–0 win over Mexico in the round of sixteen having come on as a late substitute.
In May 2019, Firmino was included in Brazil's 23-man squad for the 2019 Copa América. Firmino played all 90 minutes of the final as Brazil won 3–1 to lift their ninth Copa América title.
Roberto Firmino