Mutation induced by irradiation is an effective method for both creating germplasm resources and developing new varieties of crops. In the current study, we briefly introduced the commonly used irradiations for mutation induction, the object for mutagenic treatment and the technical methods of identification and screening  of target mutants in the mutated offsprings. Meanwhile, we summarized the main achievements of mutation breeding in crops and research progresses in mutagenesis mechanism. The imminent problems to be solved in future mutation breeding were also discussed with focusing on the improvement of the efficiency of mutation breeding in crop.