In order to avoid the inefficient or invalid polymer solution cycle，optimize oilfield chemical dosage reasonably，improve oil production and increase oil production per ton of polymer and other parameter values，the change rule of development indexes，including polymer volume，composite water cut，polymer concentration of production and increased multiple of oil，were analyzed thoroughly among each well groups in later polymer injection period in Daqing oilfield. Considering economical benefit and geological condition differences between wells and between layers，the plan of polymer injection should be stopped when the composite water cut of the block is 92%. Polymer injection should be stopped when the composite water cut of single well is 94%. For the producers with composite water cut of 92%-94%，the time of polymer injection stopping can be determined from the intersection point of the three curves：the recovery increment curve，the derivative curve of polymer consumption and the economic limit curve. Polymer injection implementation method was established as “oil layers stop while wells keeping，and wells stop while stations working，and stations stop while blocks working”. On this basis，the utilization rate of polymer and the effect of polymer flooding development will be improved.