本文根据小浪底水利枢纽工程２３６０ａＢＰ古洪水流量的推求方法及环节，进行了误差传播的推导，并根据不同的情况对各分项因子作了误差估算，从而给定了最终提交的古洪水流量的误差范围。计算结果表明，如果以砾石层顶作冲刷控制，流量误差为１３６４％；当以全新世与更新世地层的交界面砾石层作为控制，其淤积面积的４０５％作为误差范围时，流量误差达１５５４％，其全部淤积面积都作为误差范围时，流量误差可达２９６％，但存在这种误差的可能性很小 According to the methods and links of the 2360aBP ancient flood discharge of Xiaolangdi Multipurpose Project, the error propagation is deduced. According to the different conditions, the error of each sub-factor is estimated. Then the error of the ancient flood flow finally submitted is given. range. The calculation results show that the flow error is 1364% if the top of the gravel layer is used for erosion control. When the interface gravel layer of the Holocene and Pleistocene strata is controlled and 405% of the sedimentary area is taken as the error range, Flow error of 15  54%, all of its siltation area as an error range, the flow error up to 29  6%, but the possibility of such errors is small