Abstract: The present disclosure belongs to the technical field of gene editing, and specifically provides a FgTad2-FgTad3-Amel editing enzyme system, an editing tool, and an editing method. In the present disclosure, the system is a ternary complex composed of three genes (proteins), FgTAD2, FgTAD3, and AME1, and can catalyze A-to-I editing on mRNAs. Extensive A-to-I mRNA editing can be detected by expressing the AME1 gene in vegetative stage of Fusarium graminearum. Transforming the FgTad2-FgTad3-Ame1 editing enzyme system into Saccharomyces cerevisiae, Escherichia coli, and human cells to allow expression can produce A-to-I mRNA editing. This indicates that a Fusarium graminearum-derived A-to-I mRNA editing system is active and broadly adaptable, and has a great potential to be developed as a gene editing tool in different organisms.