A systematic convective weather event called the MCC (Mesoscale Convective Complex) has been noted for its mechanism of formation and appearances in the satellite pictures by many meteorologists. A great number of MCC’s have been identified in the cloud pictures over mainland China since 1978. Typical cases are the ones occurred over East China on April 12, June 8, and July 12 of 1979 and April 4,1984. Cloud picture characteristics of the formation, development and dissination of the MCC over the eastern parts of Henan and Hubei and the provinces of Jiangsu and Anhui on June 8, 1979 are analysed and its structure is investigated.