The 24-year-old holding midfielder arrived in London late in the week and underwent his medical on Friday before rubber-stamping his switch to White Hart Lane.
Sao Paulo-born Paulinho scored 34 goals in 167 games for Corinthians and has 17 caps for Brazil, including one in last Sunday's 3-0 win over Spain in the Confederations Cup final in Rio.
Paulinho becomes Spurs boss Andre Villas-Boas' first signing of the summer with the Londoners also seeing off a challenge from Spanish giants Real Madrid for his signature.
The player opted for Spurs as it seems he wanted a move to London where he will also link up with Brazil team-mate Sandro in the centre of midfield next season.
Speaking on Spurs' official Twitter account Paulinho said: "I am very happy and excited to have joined Spurs. It's a huge pleasure for my career to be at a club as big as Tottenham."