"Credit Suisse remains committed to our investment banking & capital markets clients throughout the APAC (Asia Pacific) region," the company told Reuters in response to a query.
Credit Suisse's restructuring plan includes creating a separate unit for its investment bank under the CS First Boston brand.
Reuters was not immediately able to ascertain whether the few remaining staff at Credit Suisse's Japanese investment banking division would be shifted to the new unit.
Credit Suisse also runs wealth management, equity research, securities trading and asset management businesses in Japan.
Some of the major deals that Credit Suisse advised on in Japan included Hitachi Ltd's (6501.T) $9.6 billion acquisition of U.S. software company GlobalLogic Inc.