The utility model relates to a clock device based on SDH network E1 passageway fault monitoring, including connecting synchronized clock, receive outside time base mark signal and frequency base mark signal's input unit, connect synchronized clock, at real -time supervision and the synchronization unit who carries out taming inside local clock according to time base mark signal and frequency base mark signal to the data signal of E1 passageway when statistical analysis and clock synchronization signal source are selected, and connection synchronized clock, the time signal's of time service synchronous output unit is carried out each clock of intelligent substation according to the clock data output of inside clock. The utility model discloses a device has monitoring and analysis function to SDH network 2Mbits frequency, in construction electric wire netting time integrated system, when providing high accuracy standard time for electric wire netting secondary system, intelligent substation's reliability has also been improved.