Abstract: This study carried out granularity experiment of the stream sediments from the Shapinggou super-large molybdenum ore deposit in the northern Huaiyang area. On the basis of dispersed flow length experiment, the proportion and change features of main ore-forming elements contents in different graded stream sediments were compared so as to analyze the attenuation characteristic of the main ore-forming elements. The compositions of the varied-grain stream sediments suggest that the sampling method of intercepted granularity can be applied in the survey of stream sediment measurement. This study provides a technique basis for conducting the 1:50 000 geochemical survey in the northern Huaiyang area.