The increase of futures margin 17% requires additional principal 10%. When the deposit account is less than 50% of the original deposit amount, additional deposits will be made to customers, and the excess will be charged at 10% of the principal. Under the background of the lack of clear legal norms of deposit, it is necessary to discuss the types of deposit, and define the deposit of reserve fund, advance payment, lease, decoration, deposit, deposit with return right and deposit with unparalleled return effect respectively to determine their respective legal effects.