Abstract: The pump setting depth in rod-pumped wells is always according to the relationship between pumping efficiency and submergence depth of the pump, or to submergence just by experience, through the comparative analysis of relationship among pump setting depth, pump efficiency and system efficiency, it is put forward that the best system efficiency, the maximum well fluid recovery or the best economic efficiency should be regarded as the objective function. After the comparison between multi design proposals and some optimal work, the pump setting depth which has the biggest objective function is selected as the reasonable pump depth. Transferring from flowing to pumping wells, viscous crude wells, limited but stable liquid producing wells, drainage gas recovery wells have the different well casing, the selection of objective function should be different. It has major application value for oil field exploitation.

Key words: sucker rod pump, submergence depth, pump setting depth, system efficiency, optimal design