In 1986, after graduating from the Department of Agricultural Chemistry at Kobe University, Matsunaga joined Hakutsuru Brewery. After working in various departments within Hakutsuru Brewery, he became the general manager of the Overseas Business Department and currently serves as the director in charge of Overseas Business.
In the U.S., he serves as CEO of HAKUTSURU SAKE OF AMERICA, INC. and as a board member of SAKEONE CORPORATION (Oregon), a U.S. distributor of Hakutsuru's craft sake products, where he focuses on developing the U.S. market.