Fiber ball filler is made of fiber-wire binding, which is a flexible and high performance filter material with variable porosity. Compared with the traditional rigid granular filter material, it has the advantages of good elastic effect, no floating surface, large porosity, long working cycle and small head loss. During the filtration process, it is affected by the working pressure, upper cut mud and the weight of filter material after soaking water, thus forming the distribution state of upper thin and lower dense filter layer, which adsorbs and intercepts suspended solids in water with its huge specific surface area and porosity. The voids in the filter layer gradually decrease along the direction of water flow, forming a more ideal distribution structure of voids from the top to the bottom. Therefore, it has high efficiency, fast filtration rate, large sludge capacity, good filtration effect, renewable, with gas and water backwash, washing water is 1-2% of the filtration water, suitable for all kinds of water quality filtration and fine filtration.