De Vries passed his medical on Tuesday and has signed a one year deal, though he will have a chance of an extension if he performs well.
It's a significant move.
The Auckland City FC striker joins a select bunch of players from this country to ply their trade in Japan.
Wynton Rufer was the first, scoring 25 goals in 49 games for JEF United Ichihara in 1995 and 1996.
Michael Fitzgerald has played more than 150 games in Japan since 2011, mostly for Albirex Niigata in the J League, though he is currently with Kawasaki Frontale, and Michael Den Heijer spent a year at Kashiwa Reysol at youth level.
De Vries joined Auckland City in 2013, winning two ISPS Handa Premiership titles, four OFC Champions League titles and a Nike Lunar New Year Cup among the honours he collected.
"I want to thank everyone connected with Auckland City FC for everything they've given me these past few years," said De Vries. "[The club] achieved milestones not many teams in New Zealand may ever experience."
Coach Ramon Tribulietx acknowledged De Vries was a significant loss but was also happy for his protege.
"I'm astounded this move hasn't happened sooner for a player of Ryan's quality — particularly in the last two years," said Tribulietx.
"Ryan is a player that can grow in a professional competition and environment. The reality is Ryan trained and played for us to a high standard and held down a fulltime job outside of the game. I'm pleased he has at last reached a full time professional environment where he will be able to show his potential and prove himself."
De Vries, who also won four domestic titles with Waitakere United, made his debut for the All Whites in March 2015 against South Korea.
He follows Clayton Lewis (England), Joao Moreira (Malta) and Daewook Kim (South Korea) as other former Auckland City players who have secured professional deals in the last six months.
