Kuwait currently invests about $15 to $16 billion in Japan, said Mustapha Al Shamali, who is currently on a tour of Asia with Kuwaiti Prime Minister Sheikh Nasser Al Mohammad Al Sabah, Kuna reported.
The boost in investments would follow an agreement to avoid double taxation between the two countries, which would help strengthen investment flows, Shamali said.
Both countries had agreed in principle to sign the taxation deal, he added, without saying when a final deal would be reached.
The KIA was looking at investments in Japan's real estate sector and stock market, as well as other direct investments, Shamali said, without giving details.
The wealth fund is also studying how to enhance its partnerships with European firms expanding into China, including German carmaker Daimler, Shamali said, without giving details on the nature of the partnership.
The KIA owns 7.6 per cent of Daimler, according to the carmaker's website.
KIA is also studying investment opportunities in South Korea, Shamali added.