Abstract: The flow track of filling slurry and distribution law of strength are controllable factors for influencing quality of filling materials.Taking the filling stope of Shi Rengou iron mine as engineering background，with the aid of the MDL-vs150 3D-laser scanner，the date of final state trajectory surface of filling slurry were extracted，the curve functional equation of flow track of filling slurry in stope was obtained，and the distribution law of strength was revealed by the way of site sampling and mechanics experiment in laboratory.The results showed that:with blanking hole as the origin，the curve of flow track trajectory surface of filling slurry tends to normal distribution，the strength of filling material has an “inverted-S” distribution of diminution-enlargement-diminution along the flow direction of filling slurry，strength loss area and strength increase area appear along the flow direction of filling slurry，the average loss is 25.80% and the average increase is 17.18%.The results can provide theoretical basis for the design of the amount and position of drill holes for filling，and also provide theoretical basis for stability analysis of filling material.It is a good reference to make quality assessment of cut and filling mining for similar mine.

Key words: Filling slurry, Flow track, Strength distribution, 3D-laser scanner