Abstract: In order to improve the wettability and add additional functionality to wool fibers,the effect of the three pretreatments ultrasonic water bath,ultrasonic and penetrating agent water bath,and impregnation with penetrating agent on the wettabiliy of wool fiber was investigated.The wettability and the surface morphology of the wool fibers before and after treatment were characterized with single-fiber dynamic contact angle tension meter(CDCA) and scanning electron microscope(SEM).The experimental results indicated that the wettability of worsted fabrics subjected to the three pretreatments respectively was all improved more or less,and the improvement of the wettability of worsted fabrics treated with ultrasonic and penetrating agent water bath was most significantly.SEM indicated that the surface scale layer on the wool fibers was etched and partly stripped after ultrasonic treatment.