The invention brings forward a method for removing excess calcium oxide in white mud calcium carbonate obtained through alkali recovery, specifically to a novel method for eliminating excess calcium oxide in the process of refining of conventional white mud calcium carbonate obtained through alkali recovery. According to the method, a sodium alginate solution is added in the process of grinding of white mud calcium carbonate to remove calcium oxide unreacted after completion of a causticization reaction, and then an organic acid solution is added after grinding to adjust a pH value to 8.5 to 10.5 so as to obtain a product which can be directly used for filling of paper sheets. The method not only realizes elimination of excess calcium oxide but also produces the beneficial effects of improvement of AKD glueing performance on paper and enhancement of quality and application performance of white mud calcium carbonate.