The invention belongs to the fields of microorganism breeding and fermentation engineering, and concretely relates to a Corynebacterium glutamicum, and a key tryptophan synthesis gene thereof. The above high-yielding strain is obtained through editing the genome of Corynebacterium glutamicum CGMCC No.12302 through a gene engineering means, and integrating the trpDCB mutation site in a tryptophan operon to the genome of the CGMCC No.12302. The Corynebacterium glutamicum provides a new mutation site for tryptophan synthesis related gene, and provides a new research direction for biosynthesis of the tryptophan; and a shaking bottle fermentation result shows that the tryptophan output of the obtained strain is about 3.4 times original output, so the tryptophan production performance of the strain is greatly improved.