The agreement was reached in talks between Japanese Prime Minister Shinzo Abe and Chinese Premier Li Keqiang in Tokyo on Wednesday.
China has agreed to create a more than 30-billion dollar quota for Japanese investors. This will make it easier to buy yuan-denominated financial products in mainland China.
Japan and China will also speed up talks on reviving a currency-swap agreement to provide each other with funds in a financial crisis. The deal expired in 2013.
Both nations also agreed to work to set up the first bank in Japan that can clear financial transactions in the Chinese currency.
Once the bank is up and running, Japanese companies will be able to transfer money to China more easily.