The objective of the present work is to evaluate the resistance of a laser-surface-melted 0.4% C low alloy steel to solid particle erosion. Towards this purpose, steel samples heat treated to two different base Vickers hardness levels, namely HV 350 and HV 550, were subsequently laser surface melted up to a depth of about 800 υm, resulting in hardnesses of HV 500 and HV 660 respectively. An air jet erosion tester utilizing SiC particles as erodent was used for comparing the erosion behaviour of laser-treated steels with those of untreated steel and annealed Armco iron (HV 76). Erosion tests were carried out at two impact velocities (46 and 96 m s-1) and three impact angles (30°, 60° and 90°). The results indicate that laser surface hardening does not improve the erosion resistance of a 0.4% C steel and that the erosion rates of the steels are very similar to that of annealed Armco iron. © 1993.