Tuiloma signed on Monday after jetting back to Europe from the ill-fated Oly Whites campaign in Papua New Guinea.
"I have been progressing as a player at Marseille and I am excited to continue that development," said Tuiloma.
"Marcelo Bielsa is known as one of the best coaches in the world and I am honoured to play for him and the great coaching staff that has been assembled at the club."
It's a hugely significant step. Tuiloma has been with the French team since August 2013, but was only on a youth contract. That expired last month, and there was some uncertainty over what might happen next.
Tuiloma had impressed at the club, and in February became the first Kiwi to take the field in Ligue 1, as he came off the bench in a match against Rennes.
But things can change quickly in the professional game, and all signings were put on hold while Bielsa negotiated his own future at the club.
That meant Tuiloma had to captain the Junior All Whites in the Under-20 World Cup, and also play for the Oly-Whites, with his future up in the air.
Now he has a three-year professional contract, putting him in the top echelon of Kiwis in Europe, alongside Winston Reid, Chris Wood, Tommy Smith, Ryan Thomas and Marco Rojas. It caps a remarkable rise for Tuiloma. A little more than two years ago he was still playing Northern League football in New Zealand, and had never been in a professional training environment.
Now he's got three years in France ahead of him, under one of the most renowned managers in the world.
The improvement in Tuiloma has been particularly noticeable over the past 12 months; he was a step ahead of most of his teammates at the Under-20 World Cup, able to find time and space where others couldn't.
"Olympic Marseille as an organisation has been amazing," said Tuiloma. "The club has taken great care of me, from the President to the support staff, to all of the coaches. I have learned so much from my teammates as well. The level of play is world class and every day I pick up something new. The people of France have also been great ... [and] I feel like France is my second home."
Tuiloma also paid tribute to the support from his parents over the years, as well as his US-based agents, who he described as "like family".
Ligue 1 starts in three weeks.
- By Michael Burgess of the Herald on Sunday
