Abstract: The accurate value of the network parameters is essential for power system monitoring and control center. However, these parameters stored in the control databases may contain erroneous ones or their actual value deviated from the original value due to the long-time operation and the aging of transmission lines. This paper proposes a method for estimating the erroneous parameters with Supervisory Control and Data Acquisition(SCADA) measurements only. The main idea is to set parameters as state vectors instead of voltage. In addition, the reliable parameters in the local area is added as the pseudo measurement to the measurement equation, which improves the redundancy of measurement. The effectiveness of the proposed method is tested in the IEEE 118-bus system.