Yakuza 6: The Song of Life is already out in Japan, with a North American release coming in early 2018. The game was billed as the end of the story of Kazuma Kiryu, the protagonist of the numbered, mainline Yakuza games. While Sega will be sticking to that, there will be more Yakuza coming in the future.
At the Famitsu Awards, Yakuza series director Toshihiro Nagoshi confirmed that a new Yakuza title is coming. The news was reported by Games Talk (translated via Gematsu), who noted that the team will be sticking to Kiryu's retirement.
Nagoshi said that his desire is to make a new Yakuza game, and even admits that it doesn't have to be limited to a single entry. He said the team created the all-new Dragon Engine for Yakuza 6, but the engine will be fully-completed with subsequent releases.
"I'm already working on the next title. In the not too distant future... I think there will be an opportunity to talk about the next game's development in a relatively early stage," Nagoshi reportedly said.
In the mean time, we still have Yakuza Kiwami coming on August 29 and Yakuza 6 all the way in 2018.