A method for synchronizing clock in a synchronous network, comprising the steps of: receiving, by a slave clock side equipment, a synchronization message sent from a master clock side equipment; recording, by the slave clock side equipment, a sending time of the synchronization message as a first time t1, and a receiving time of the synchronization message as a second time t2; performing a time adjustment on the slave clock side equipment to obtain an adjusted clock time t, wherein t = to - (t2 - t1),wherein to is the original clock time of the slave clock side equipment; sending, by the slave clock side equipment, a delay request message to the master clock side equipment, and recording a sending time of the delay request message as a third time t3; receiving the delay request message by the master clock side equipment and recording the receiving time of the delay request message as a fourth time t4; receiving, by the slave clock side equipment, a delay response information from the master clock side equipment, wherein the delay response information does comprise the receiving time of the sent delay request message as the fourth time t4; calculating, by the slave clock side equipment, a path delay time td between the master clock side equipment and the slave click side equipment, wherein td = (t4 - t3)/2; and re-adjusting the adjusted clock time of the slave clock side equipment according to the calculated path delay time td, wherein the clock time of the slave clock side equipment is re-adjusted by adding one td on the basis of current clock time of the slave clock side equipment: the method for synchronizing clock is characterized by detecting, by the slave clock side equipment, a running state of a local network element; and notifying, by the slave clock side equipment, a slave clock side processing unit of the slave clock side equipment to stop performing a clock synchronization related operation, when detecting that the running state of a local network element is abnormal. receiving, by a slave clock side equipment, a synchronization message sent from a master clock side equipment; recording, by the slave clock side equipment, a sending time of the synchronization message as a first time t1, and a receiving time of the synchronization message as a second time t2; performing a time adjustment on the slave clock side equipment to obtain an adjusted clock time t, wherein t = to - (t2 - t1),wherein to is the original clock time of the slave clock side equipment; sending, by the slave clock side equipment, a delay request message to the master clock side equipment, and recording a sending time of the delay request message as a third time t3; receiving the delay request message by the master clock side equipment and recording the receiving time of the delay request message as a fourth time t4; receiving, by the slave clock side equipment, a delay response information from the master clock side equipment, wherein the delay response information does comprise the receiving time of the sent delay request message as the fourth time t4; calculating, by the slave clock side equipment, a path delay time td between the master clock side equipment and the slave click side equipment, wherein td = (t4 - t3)/2; and re-adjusting the adjusted clock time of the slave clock side equipment according to the calculated path delay time td, wherein the clock time of the slave clock side equipment is re-adjusted by adding one td on the basis of current clock time of the slave clock side equipment: the method for synchronizing clock is characterized by detecting, by the slave clock side equipment, a running state of a local network element; and notifying, by the slave clock side equipment, a slave clock side processing unit of the slave clock side equipment to stop performing a clock synchronization related operation, when detecting that the running state of a local network element is abnormal. the method for synchronizing clock is characterized by detecting, by the slave clock side equipment, a running state of a local network element; and notifying, by the slave clock side equipment, a slave clock side processing unit of the slave clock side equipment to stop performing a clock synchronization related operation, when detecting that the running state of a local network element is abnormal.