The paper aims to study the effect of magnetic fluid polarity on the tribological properties of smooth and textured surface of titanium alloy. The friction and wear experiments of smooth and textured surfaces of titanium alloy are carried out on UMT-3 friction and wear tester with water-based ferrofluid, kerosene-based ferrofluid, deionized water and kerosene as lubricants. The effects of magnetic particles with different polarity on friction coefficient, wear amount and wear morphology of different surfaces are obtained. The results show that:on the smooth surface of titanium alloy, the friction coefficient decreases by 8.42% and the wear scar width decreases by 8.47%. The non-polar magnetic particles increase the friction coefficient by 33.94% and the wear scar width by 42.20%. The wear mode changes from slight adhesive wear to severe abrasive wear. On the textured surface, the friction reducing effect of polar magnetic particles is further enhanced, while that of non-polar magnetic particles is not obvious. When lubricated by different polarity magnetic fluid, the polar magnetic particles will be more easily adsorbed on the surface of titanium alloy, thus increasing the thickness and stiffness of oil film and reducing the friction coefficient.