With the SVD(Singular Value Decomposition), wavelet transform, the multiple temporal scale feature of coupling relationship between rainfalls in the first flood season in South China and 500hPa geopotential height is investigated. Results indicate that rainfall-height coupled mode appears pronounced interannual difference, and various periodic variability. Characterized by the multiple level and multiple temporal scale, a lot of coincident periods between rainfall and Height field indicate the closed couple relationship between them, besides, they all appear decadal abrupt.