Abstract: X-ray digital radiography has been widely utilized in power systems due to its technical advantages including visualization and non-destructive features to equipment. This paper introduces a fault of excessive loop resistance in 220 kV gas-insulated switchgear and analyzes different strategies and methods for locating the fault points. Finally, the X-ray digital radiography is used to locate the fault point accurately and rapidly, with or without power outage or with minimal power outage. It compensates for the shortcomings of the existing routine detection methods, namely lack of intuitiveness and difficulty in defect location.