Newcastle have signed Joelinton for a club-record £40m from Hoffenheim on a six-year deal.
Joelinton's arrival at St James' Park sees Newcastle break their transfer record for the second time in seven months, with the fee for the 22-year-old striker surpassing the £21m the club paid for Miguel Almiron in January.
The deal also represents a record sale for Hoffenheim, surpassing the £29m they received from Liverpool for forward Roberto Firmino in 2015.
"I'm really happy to be here," Joelinton said, who will wear the club's No 9 shirt. "I know it's a large investment that the club has made in me, and that comes with a huge responsibility.
"I'm highly motivated and hope to give back on the pitch."
Newcastle head coach Steve Bruce added: "The kid's got an exciting time ahead of him. He's a smashing young player and we're obviously delighted to get him. It's been going on for a little bit now, so to get him is great for everybody.
"He's got everything that a modern-day player wants. He's big, strong and athletic, and of course he's got age on his side too which is vitally important.
"He's learned the history and wanted it (the No 9 shirt), and that's always a big shirt to fill. But in his eyes, it was 'bring it on - it's what I'm here for'.
"He's risen to that challenge, and I'm sure he will be a big, big favourite of the supporters. He's got an incredible work-rate about him, he's got a really good humility about him, and all the attributes a top striker needs."
Joelinton, who has been capped at U17 level by Brazil, could play in Newcastle's pre-season friendly at Preston on Saturday. He scored 11 goals in 35 appearances for Bundesliga club Hoffenheim in all competitions last season.
The 22-year-old becomes Bruce's first signing as Newcastle head coach and will bolster the club's forward options following the departures of Ayoze Perez and Joselu to Leicester and Deportivo respectively.
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