IEEE1588 defines a precision time protocol (PTP) for networked measurement and control systems, which supports system-wide synchronization accuracy in the sub-microsecond range. This paper introduces the principle of high precision clock synchronization and the PTP clock models defined in IEEE1588 standard. According to topological structure of substation communication network conforming to IEC61850 standard, application schemes of IEEE1588 in digital substation are proposed, and their advantages and disadvantages are also discussed. Then the redundancy configuration method of clock unit and its function implement are given. Clock synchronization error of IEEE1588 standard is theoretically analyzed. At last, concrete system wide application strategies of IEEE1588 standard in area power network are researched.