Tsuyoshi Hyokai serves as Deputy Director General for Finance and Research Planning at ERIA. He has extensive professional experience in international finance at the Japanese Ministry of Finance. In particular, in the field of development finance, he was responsible for debt issues affecting developing countries, including Paris Club matters, bilateral development finance, and assistance provided through multilateral development banks, including the World Bank Group and the Asian Development Bank (ADB). He also handled matters relating to financial sanctions and economic security under the Japanese Foreign Exchange and Foreign Trade Act (FEFTA).

In Japan's domestic financial sector, he has experience analysing the Japanese Government Bond market and was also involved in the supervision of regional banks in the Tokyo metropolitan area.

Prior to joining ERIA, he served as Director for Climate Change and Environmental Issues at the Japanese Ministry of Finance, leading discussions on climate change and environmental issues in the G7 and G20 finance tracks. He also served as a Council Member of the Global Environment Facility (GEF) and a Committee Member of the Climate Investment Funds (CIF).

Outside the Ministry, he has worked at the Embassy of Japan in France (Paris) as a Financial Attaché, at the Asian Development Bank Institute (Tokyo, Japan), where he coordinated budgeting, human resources, and accounting, and at the World Bank (Washington, D.C., USA) as Senior Advisor to the Executive Director for Japan.