The present invention discloses a method, system and device for determining a bandwidth of an uplink sounding reference signal SRS. The method for determining the bandwidth of the uplink SRS comprises the following steps: determining whether SRS is transmitted with the uplink pilot time slot if the SRS is transmitted with the largest bandwidth level; transmitting SRS with the non-extensive SRS bandwidth if SRS is determined to be transmitted with the uplink pilot time slot and the UE reaches the power limit. In the present invention, the signal-to-noise ratio detected on the bandwidth with which SRS transmitted can be maintained, and the accurate detection of the channel information is thereby realized.