Abstract: Developing superfine fiber filter is one of the main technical methods to control PM2.5. An experimental setup was used according to the national standards， and the filtration performance of sea-island-fiber filters was studied comprehensively.Such parameters as the filter efficiency of filter material， the residual resistance and the ash cleaning cycle were obtained， and a comparison was made with the traditional needle felt filters and membrane filters. The results showed that the counting efficiency of sea-island-fiber filters for PM2.5 is 94.9%， which is far higher than that of the traditional filters and similar to that of the membrane filters; meanwhile， the residual resistance of the dynamic filtration process is lower than that of the membrane filters， the residual resistance increases slowly， and the ash cleaning cycle becomes longer， which is conducive to prolonging the filterlife and saving cost.

Key words: sea-island fiber filter, PM2.5, filtration efficiency, ash cleaning cycle, residual resistance