Abstract. The nanofiber based filtering material, made up of fibers of diameter less than 1000 nm, have been discovered as new filtering material for effective filtrations. Lyocell fiber is a kind of regenerated fiber which can be easily fibrillated and brought no negative impact on the recovery of filter material.The present study focuses on how the Lyocell fiber changes with the intensity of beating and compares the effect of nano-fibrillated Lyocell fiber（61°SR） and micro glass fiber（44°SR） on the properties of filter material. The results show that the length, diameter, distortion and degree of fibrillation of Lyocell fiber changes obviously by beating, and a mass of nano-fibril appeared after intensive beating. At the same time, the air permeability and pore size distribution is similar when the content of fibrillated Lyocell fiber and micro glass fiber are the same in filter material; What’s more, the strength of filter material increases with the percentage of fibrillated Lyocell fiber increasing, But the micro glass gets an opposite trend. The burst strength of the filter material with 20 wt.% fibrillated Lyocell fiber is 336KPa, with 20 wt.% micro glass fiber is 71KPa.This study has shed some light on the application of Lyocell fiber to improve the accuracy of filter material effectively.