In order to solve oilfield pumping system with the following disadvantages:low efficiency of crude exploitation, high energy consumption, etc. Kinetic and efficiency model of pumping system has been established to calculate the pumping rod load and efficiency. A new power system transmission solution has been proposed, which use spring group to store pumping system deceleration inertial energy. Spring group releases energy when pumping system changes direction. Adding spring energy storage device reduces the impact of electrical motors' working status switch, and saves system energy consumption substantially. Spring energy-storage device designed in this paper can reduce motor torque ripple, short start-up time, and reduce motor heating, extend motor life. Compared with traditional reciprocating pumping unit, the new-designed oil-pumping system has great improvement, the energy saving rate reaches 10.46%.