In this paper, TC4 titanium alloy surfaces were strengthened by electro-spark alloying (ESA) with the tungsten rod as an electrode to investigate the effects of voltage and pulse frequency on tribological properties of tungsten-strengthened layers. It was shown that the surface morphology of strengthened TC4 possesses a main tungsten phase with a typical characteristic of sputtering. The maximum average thickness and microhardness of strengthened layers had been achieved at 50 μm and 21.6 GPa, respectively. The latter had been found to be 6-7 folds higher as opposed to that of TC4. In the friction tests conducted, the friction coefficient and wear loss of strengthened layers appeared to be reduced by approximately 76.2% from 0.45 to0.11, as well as 89.47% from 3.8 to 0.4 mg accordingly. Overall, this study offers an effective preparation method of wear-resistant tungsten-strengthened layers with the resulting low friction coefficient on TC4 surfaces via ESA.