Abstract: To demonstrate the load reducing ability and feasibility of deep pumping of the lateral-flow deep pump, on the basis of analyzing the working principle and stress state of this kind of pump, a polished load calculating model is established for deep pumping of oil wells. By comparing it with that of the commonly-used tube pump, it is found that the new deep pump could reduce the load when running up and down. Through the calculation of the X839 well, the load reduction effect of the new deep pump is proved. The calculation shows that the new deep pump could reduce the maximum and minimum loads by one ton or so as compared to the commonly-used one. This could be valuable reference to the wide application of later-flow pumps to deep pumping wells in oilfields.