Abstract: Using radar, satellite, available intensive observations, rawinsonde data and NCEP daily reanalysis data, the evolution characteristics and affecting systems of the MCSs producing heavy rain in Huaihe valley from July 8 to 9 in 2007 are analyzed. The results show the excessive heavy rain is caused by three MCSs, and their modes are Training line/Adjoining stratiform MCS, Leading stratiform MCS and Embedded Line MCS respectively. The radar echoes for those MCSs are organized well, and some MCSs are moving, others are quasi-stationary. The echo distributions of MCSs indicate the precipitation areas. The corresponding synoptic conditions of MCSs are cold front and inverted trough, the frontal surface and surface convergence line respectively. Corresponded with the wind, field the flow field or height flied in low-middle troposphere represents two low vortexes. As the development of the vortexes, the areas where MCSs occurred are corresponding to the flow convergence areas.