In this paper, a kind of pratical adjustment method that disposes the data of level net observed in different periods as whole is introduced. It is overall adjustment with piecewise velocity models. The adjustment can solve deformation velocities of different Periods on uniform datum and reflect kinematic evolutional process of the vertical deformation field as whole. The model of the adjustment is a general adjUstment of indirect observations from level net,because it contains traditional static adjustment and traditional dynamic adjustment with velocity models. The characteristic of the adjustment is analysed,the algorithm and program composition to solve the enormous normal equation in the adjustment is introduced,and an example is given.