To improve the low moisture regain and the static electricity of polyacrylonitrile(PAN) fiber, quacternary ammonium salts such as 3-(trimethoxysilyl) propyl dimethyl octadecylammo-nium chtoride(SAC) and alkylbenzyl dimethylammonium chloride(BAC) were mixed with PAN m DMF. As the increase of content of salts, the moisture regain increased and the static charge decreased significantly. The contact angle of modified PAN decreased with increasing BAC content, however the contact angle increased with increase of SAC content for the water repellent surface property. The results of reduction rates of colonies showed good antimicrobial activity of salts.