Improvement of tribological properties has been studied for slide pin of vacuum circuit breaker by surface modification. Surface modified slide pin were coated with the following three different methods. (I) DLC thin film deposited with ion plating (II) TiN thin film deposited with physical vapor deposition (PVD) (III) Sn layer coated with micro shot peening (MSP). The evaluations of Tribological properties for surface modified slide pins were experimentally carried out. As the results, the friction evaluation shows that TiN and Sn coated slide pins don't reduce the friction coefficient and wear compared to Virgin (uncoated) materials, but DLC coated slide pin markedly reduce the friction coefficient and wear compared to Virgin (uncoated) materials, DLC coated slide pin indicated miniaturization and cost reduction of vacuum circuit breaker.