This paper presents the fault detection technique in wide area power system network using Phasor Data Concentrator (PDC). Single line to ground (SLG) fault data of transmission line is processed using the WAMS technology. Phasor Data Concentrator (PDC) is primarily data collecting centres located at the control centre processing unit and is responsible for collecting all the PMUs data that is transmitted over the communication link, which will detect fault in transmission line. This will help the operators in control centre to monitor the health of wide area power system network, and can initiate corrective actions when time is the critical issue. In this paper, the voltage and current phasor information, and other transmission line parameters from 14 IEEE bus system is processed and detects the fault in transmission lines. The proposed fault detection technique in transmission line of wide area power system network is very useful for improving power system reliability and power quality.