Because of the large-scale integration of wind power，the dynamic characteristics of power system havemany uncertain effects.Based on deterministic analysis methods，traditional on-line security assessment systemcannot quantitatively estimate the actual operating conditions of the power system for only considering the mostserious and credible accidents.Therefore，the risk theory is introduced into an on-line security assessment systemand then an on-line risk assessment system for wind power is designed and implemented by combining with thedynamic security assessment system.Based on multiple data integration，the wind power disturbance probability isavailable and the security assessment of the power grid can obtain security indices in different aspects.The operatingrisk index is an expectation of severity，computed by summing up all the products of the result probability and itsseverity.Analysis results are reported to the dispatchers in on-line environment，while the comprehensive weaklinks are automatically provided to the power dispatching center.The risk assessment system in operation can verifythe reasonableness of the system.