Neymar, 33, helped Santos beat fourth division Agua Santa 3-1 in a Sao Paulo state championship match
Neymar returns to Santos after playing just seven times for Saudi Arabia's Al Hilal despite a reported salary of around $104 million a year.
Santos' president told Brazilian superstar Neymar it was "time to return to (his) people" in a video published on social media on Tuesday.
Brazilian star Neymar on Monday ended his injury-plagued 18 month stay in Saudi Arabia as his club, Al-Hilal said they had "agreed to terminate the player's contract by mutual consent".
Neymar has had an injury-plagued stay in Saudi Arabia, playing just seven times despite a reported salary of around $104 million a year.
Brazilian striker Neymar said that former PSG teammate Kylian Mbappe became "jealous" of his relationship with Lionel Messi when the superstar joined the club.
Inter Miami coach Javier Mascherano expects to bring in several new faces to support Lionel Messi in Major League Soccer next season but says it is "impossible to think about" Brazilian Neymar being one of them
Lionel Messi and Inter Miami will kick off FIFA's new 32-team Club World Cup when the Major League Soccer side take on Egypt's Al Ahly in the June 15 opener
Aleksandar Mitrovic scored three times on Monday as Saudi Arabia's Al Hilal beat Iranian side Esteghlal in the AFC Champions Elite to maintain their 100 percent start to the competition
Tottenham teenager Mikey Moore was compared to Brazilian ace Neymar after a standout role in the 1-0 win over AZ Alkmaar in the Europa League on Thursday.