Pineapple juices pretreated by pectin enzyme were clarified by different pore size ceramic membranes in the same conditions.The experiment results showed that:under the conditions of 30℃,the transmembrane pressure of 0.15MPa and the feed flux of 11.88L/min,the average permeate flux of 0.6μm、0.2pro、0.1μm and 0.05μm ceramic membranes were respectively 150.12L/(m2· h)、61.77L/(m2· h)、52.99L/(m2· h)and 44.18L/ (m2· h); the transmittance and absorbance of clarified pineapple juices all reached to above 99.5% and below 0.1;the changes of the soluble solids and pH of pineapple juices was no noticeable,but the ranges of maintained vitamin C,glucose content,amino acids nitrogen and total acid of clarified pineapple juices were all between 75% and 85%,both the reserved protein and pectin were between 0.5% and 36.4%;0.6μm membrane could not effective to segregate microorganisms,but 0.2μm and 0.1μm membrane could effectively remove the standard plate counts of juice above 98.5%,and totally segregate molds and yeast,also make coliform get up to nation standards (lower than 0.3MPN/mL).