Abstract: The statistical method was employed to compare the microfiltration effects of the three kinds of self-made fly-ash ceramic membranes on apple juice and the membrane fouling mechanisms were studied preliminarily. Using membranes with different pore sizes ( 2.13, 1.25, 0.30 μm) , it showed that after the microfiltration, there were significant improvements in juice color and the clarity were increased, respectively. Meanwhile, the content of protein and polyphenol that lead to turbidity were induced.Other important properties like TSS, p H, and density were almost unaffected. The three membranes were controlled by different mechanisms. Experimental results showed that the membrane of pore size 1.25 μm proved to be optimal for the microfiltration of apple juice.The fly-ash ceramic membrane has good application prospect to the microfiltration of the apple juice.