Abstract: Using conventional observational data, radar data, satellite images and so on, the excessive rain in northeast Hubei province on 1 July 2008 is comprehensively analyzed focusing on the occurrence and development of mesoscale disturbance system, the structure characteristics of the heavy rain mesoscale convective system, and the terrain effect on mesoscale system. The results show that heavy rain in northeast Hubei province is closely related to the occurrence and development of mesoscale disturbance system. The successive eastward movement of the meso-β-scale convective systems stimulated by the mesoscale cyclone wave cold shear exactly results in the excessive rain in Hongan.The mesoscale cyclone is formed in the developmental stage of Huanghuai front cyclone wave, which developmental process can be well revealed by the form and structural feature of radar reflectivity factor. The cold air moves southward between the Dabie mountain and Tongbo mountain, joins with the southwest stream of synoptic scale, results in the local mesoscal convergence line, which is the mechanism for the easy enhancement of convection in the west Hongan. By the composition of daughter clouds in different growing period, the MCS producing excessive rain shapes finger cloud in infrared cloud imagery, and remarkably features the cloud cluster which emergences the sustained heavy rain.