Neymar promised to win "lots of trophies" after receiving a warm welcome as he was introduced to Paris St-Germain supporters on Saturday.
The Brazil forward, 25, joined the French club from Barcelona for a fee of 222m euros (£200m) and he will earn 45m euros (£40.7m) a year.
"I'm delighted to be here for this new challenge," said Neymar as he appeared at the Parc des Princes.
I didn't come to PSG to be the star - Neymar speaks to BBC Sport
PSG beat Amiens 2-0 in their first league match but Neymar did not play.
The world's most expensive player watched from the stands because his international transfer certificate was not lodged in time for him to feature in the match.
Neymar added: "I want to win lots of trophies with you and I need your support to win these trophies."
PSG, six times champions of France, were runners-up to Monaco last season but opened the scoring against Amiens through Uruguay forward Edinson Cavani.
Cavani then turned provider as he set up Javier Pastore to make it 2-0.