Abstract: A big error might occur when traditional standard method is used to evaluate the scaling behavior of oilfield produced water containing polymer. This is due to the competition of polymer and EDTA to chelating aqueous calcium ions. In this paper, a novel method was proposed to evaluate the scaling behavior of oilfield produced water containing polymer. The weight of scale could be measured directly by this method. Also, the influencing of polymer concentration and molecular weight in oilfield produced water on the scaling behavior was researched systematically combining with the chelatometry, which is used to measure the concentration of free calcium ion in the solution according to the related standards.It is shown that the polymer concentration and molecular weight have remarkable influence on scaling which is due to the chelating ability of polymer's amide group to calcium ion.