Abstract: In this paper, the seepage in unsteady well flow domain is analysed by the similarity method, in which the discharge is taken as an unknown function. This method is also applicable to the problems of pumping (watering) at constant or inconstant rate in fully penetrating well or partially penetrating well. Then not only the problem of queer dot at the well bore is avoided, but also the radius of influence domain (R) of the depression cone is convenient to deduce.