Reservoir for fuel tank

The invention relates to a reservoir for a fuel tank, and the objective is to provide a reservoir for a fuel tank which is capable of being easily maintained by effectively preventing foreign materials in fuel from being introduced into a pump of a fuel transferring pipe. The reservoir for a fuel tank is a reservoir disposed in the fuel tank and comprises a containing part connected to a fuel transferring pipe supplying fuel to a motor, a pump disposed on the fuel pipe and transferring fuel from the containing part to the motor, a supplying part connected to the containing part and supplying the fuel in the fuel tank to the containing part, and a measuring part which measures the amount of fuel in the containing part. The measuring part characterized by comprising a filter disposed on a suction part of the pump and filtering foreign materials, and a prefilter which disposed to make the supplying part contained inside thereof.