Electrospun-poly(vinylidenefluoride cohexafluoro- propylene) (PVDF-HFP) micro-fiber membrane is modified by cyclonic atmospheric pressure plasma. The gas phase temperature of cyclonic atmospheric pressure plasma state was around 30℃ to 90℃, indicating this plasma can treat electrospun PVDF-HFP membrane without harmful heat damages. The surface properties of cyclonic atmospheric pressure plasma- treated electrospun PVDF-HFP micro-fiber membranes were examined by the static contact angle analysis. The influence of plasma treatment time on the electrospun PVDF-HFP micro- fiber membrane surface was studied. It was found that such cyclonic atmospheric pressure plasma is useful in PVDF-HFP micro-fiber membrane surface modification, the reduced water contact angle was observed from 137° to less than 30° with only 1 min. treatment time. Scanning electron microscopy (SEM) was used to determine the changes in surface feature of the PVDF- HFP micro-fiber membrane due to plasma treatment. In this investigation, it shows an innovative method for electrospun micro-fiber membrane surface modification by cyclonic atmospheric pressure plasma.