Abstract: Impacts of orientation of slopes and elevation in some mountatious areas are complicated.In North China,mountainous region may be divided into 14 sub-regions according to the variations of different parameters of rainfall with elevation.The variation of rainfall with the local elevation shows an increasing tendency of logarthmic function while the variation of rainfall with macro-regional height shows a decreasing tendency of exponential function.On the basis of sub-regions,the variations of the distrubusions of rainfall in mountainous regions may be expressed as a linear function of geographical coordinates:P_i= a_0i+a_1iψ+a_2iλ+a_3ih where P_i is the rainfall calculated.a_0i is a constant,a_1i,,a_2i,a_3i are the partial correlation coefficients,ψ is the latitude,λ is the longitude and h is the height.The maximum rainfall height often occurs in the range of a warm and wet air current forced to rise.The wetter this current is,the lower the maximum rainfall hight is,vice versa.