The fault analysis relies on the wave record and logic diagram of relay protection. Due to the lack of protection logic diagram format standard definition and a unified analysis tool, complex fault analysis depends on protection factory. This paper presents an expression way of protection logic diagram based on SVG graphics. The standard logic diagram is formed by inputting logic cell, operator, connecting lines, etc., through standardized definition. The fault analysis is completed by the standardized recorded wave files and SVG file. The scheme proposed has been used in line protection device, which proves the feasibility of the scheme.