On November 4， 2006， a large scope blackout was occurred in 8 countries of Western Europe， which is the most serious failure in Europe in the recent 30 years. Union for the Co-ordination of Transmission of Electricity（UCTE）and E.ON Corporation released their reports of investigations successively. This paper introduces the case and its analysis of“11·4” blackout， and discusses these reports， brings forward some methods to strengthen operation. At last， it is indicated that developing and application of dynamic SCADA system will be valid to avoid cascading failure and improve operation reliability.