Commercial banks. According to the legal network, China's Securities Investment Fund Law stipulates that the fund custodian should be a legally established commercial bank with fund custody qualifications. Fund custodian refers to the institution entrusted with the custody of fund assets and needs to supervise the daily investment operation of fund managers. The fund custodian is a banking institution. The fund custodian independently opens a fund asset account, carries out liquidation and delivery according to the instructions of the manager, keeps the fund assets, supervises the fund within a certain range, and collects a certain custody fee.