A kind of blade mechanisms of grass trimmer include a tool apron, two limit assemblies and two blades. The grade blades are two rotation sections for separatably being installed fixed what tool apron respectively by the grade limit assemblies, through the tool apron, this etc. limit assemblies and this etc. blades connecting structure design, when so that the utility model blade mechanisms repairing, it is not required to entirely separate grass trimmer, it only needs individually to change the grade blades, it is a kind of innovation and quite practical blade mechanisms design so grass trimmer maintenance cost and time cost can be greatly reduced.一種割草機之刀片機構，包含一刀座、兩個限位組件，及兩個刀片。該等刀片是可脫離地被該等限位組件分別安裝固定於刀座的兩個旋轉區段，透過該刀座、該等限位組件與該等刀片之組接結構設計，使得本新型該刀片機構維修時，不需整個拆離割草機，僅需單獨拆換該等刀片，所以可大幅降低割草機維護成本與時間成本，是一種創新且相當實用的刀片機構設計。
