The influence of rare earth( RE) content on mechanical properties and abrasion resistance of low chromium semi-steel was studied by means of metallographic examination,scanning electron microscopic examination and mechanical property test. The experiment results show that RE can improve the comprehensive properties,especially in combination with proper heat treatment. The optimum properties of low chromium semi-steel modified by RE of 0. 25 % could be obtained by normalization at 950 ℃ for 3 h. The main reason is the change in morphology and distribution of eutectic carbide and the precipitation of granular carbides. The influence of rare earth (RE) content on mechanical properties and abrasion resistance of low chromium semi-steel was studied by means of metallographic examination, scanning electron microscopic examination and mechanical property test. The experiment results show that RE can improve the comprehensive properties, especially in combination with proper heat treatment. The optimum properties of low chromium semi-steel modified by RE of 0.25% could be obtained by normalization at 950 ° C for 3 h. The main reason is the change in morphology and distribution of eutectic carbide and the precipitation of granular carbides.