Sliding wear behavior of in situ Cu-TiB2 nanocomposites fabricated by reaction of pure titanium and copper-boron melts were investigated on a pin-on-disk wear tester under dry sliding conditions, rubbing against medium carbon steel disk at sliding speeds range from 0.089 to 0.445ms−1 and at loads between 20 and 140 N. The hardness, yield strength and wear resistance of the in situ composites increased with the content (from 0.5 to 2.5 wt.%) of TiB2 nanoparticles in the copper matrix. Owing to the good interfacial bonding between uniformly dispersed TiB2 nanoparticles and the copper matrix, there was no transition from mild wear to severe wear over the applied load range. While the electrical conductivity of the in situ composites decreased considerably with the content of TiB2 nanoparticles, the wear resistance made the material a potential candidate for sliding electrical contacts.