Abstract: Provided is a genome editing system and method for gene editing at least one target sequence in a cell genome. The genome editing system comprises: (1) an expression construct comprising a Cas12f nuclease; and (2) an expression DNA sequence comprising a guide RNA corresponding to the Cas12f nuclease, and an expression construct of the targeting sequence of the target sequence. The gene editing system or method can accurately knock out a target gene from within a cell; in addition, in an in vitro cutting experiment, the target gene can be accurately cut.