Objective: To study the relationship between the sequence structure and function of a peroxidase gene (POD) and mine and confirm SSR locus of this gene in Senecio scandens. Methods: A POD gene was obtained from full-length cDNA library of S. scandens. Then a series of online bioinformatics tools were used to analyze nucleic acid sequence and amino acid structure of this gene. According to its nucleotide sequence, one SSR locus was searched and a pair of primers were designed. The PAGE electrophoresis confirmed that this primer pair had polymorphism among several landraces. Results: The target gene had the structural characteristics of typical PODs. It showed a high conservation in functional domains. PAGE electrophoresis showed that the primer could be stably amplified in different landraces with obvious polymorphisms. Conclusion: The results expanded the understanding of the function and sequence of a POD in S. scandens. The newly developed marker could be effectively applied to the detection of POD gene and breeding projects, and it also provided reference for POD researches of other species.