Some typical laser post-treatment methods for oriented silicon steel were introduced and compared each other, the effects of laser post-treatment on the oriented silicon steel were analyzed and the mechanism of refining domain structure, hence reducing the total core loss of oriented silicon steel by laser scribing (LS) method and local laser surface alloying(LLSA) method was studied. On the base, a laser nitriding method (LN method) is given. The results show that after laser treatment, domain structure of oriented silicon steel was refined, especially after laser nitriding treatment, not only the domain structure was refined, and the core loss was reduced, but also the aging property was improved and the evenness of oriented silicon steel kept well.