The work aims to improve abrasion resistance of high chromium iron. CO2 laser was applied to surface laser-quenchingof high chromium iron sample. Under the condition of abrasive medium, tribological properties of sample subject to laser quenching were studied on MMW-1A-type tester. Surface friction coefficient and wear rate of the sample were measured and analyzed. Surface micro-structure of the samplewas refined by laser quenching, which could be divided into three zones from the surface to the center, namely, quenched zone, heat affected transitionzone and substrate zone. Compared with the substrate, hardness of the quenched layer was enhanced greatly. The maximum hardness up to 1105.7HV was present on the subsurface. When the friction-wear test reached a steady state, friction coefficient of the quenched sample surface was lower than that of the unquenched one. The friction coefficient was about 0.3 (the minimum)at the quenching zoneintervalof 1 mm while that of the unquenched onewas up to 0.65. Provided with the same wear duration, wear rate of the laser quenched sample was lower than that of the unquenched one. Minimum friction coefficient and optimum abrasion resistance were obtained at the quenching zone interval of 1 mm. The laser quenching technology can effectively improve abrasion resistance of high chromium cast iron, and prolong service life of mud pump cylinder.