Fuente: WIPO "tobacco agriculture" The invention provides a codominant SSR (Simple Sequence Repeat) marker closely linked with a tobacco chlorogenic acid gene qChlA and an application method of the codominant SSR marker. The serial numbers of the codominant SSR marker closely linked with the tobacco chlorogenic acid gene qChlA are TMy80887 and TMy80891, and the nucleotide sequences of PCR (Polymerase Chain Reaction) amplification products of the codominant SSR marker closely linked with the tobacco chlorogenic acid gene qChlA are respectively shown as SEQ ID No. 1, SEQ ID No. 2, SEQ ID No. 3 and SEQ ID No. 4. The application is the application of the codominant SSR marker closely linked with the tobacco chlorogenic acid gene qChlA in detecting whether the tobacco chlorogenic acid gene qChlA exists in tobacco genome DNA (Deoxyribose Nucleic Acid) or not. Compared with a method in the prior art, the codominant SSR marker has the characteristics of accuracy, high efficiency, stability, convenience, low cost and no detection opportunity limitation, so that the molecular marker can be applied to auxiliary selection of the chlorogenic acid gene qChlA molecular marker in tobacco breeding.