Abstract: Ultra-high grade refers to the abnormal grade which is many times higher than the general grade in the geological body with uneven mineralization.Based on a large number of previous studies on the application of probability statistics distribution to ultra-high grade processing,this paper studies the selection methods of ultra-high grade upper limit in geostatistical resource estimation,and discusses the advantages and disadvantages of various methods.Empirical cumulative distribution funcion curve is used to determine the upper limit of ultra-high grade.Taking into account the missing verification steps in previous use of the method,Siche’s estimation method is used to verify the rationality of the selection of the upper limit of ultra-high grade according to the requirements of the current specification.Compared with the traditional method,the geostatistics method for ultra-high grade processing has the advantages of simple calculation steps,easy verification method,high real-time degree and high sensitivity.