Abstract: Abstract: 【OBJECTIVE】To obtain Sequence-related amplified polymorphism (SRAP) fingerprints of Cymbidium goeringii, the factors influencing the SRAP reaction system were studied【METHOD】The major components of SRAP,such as concentrations of Mg2+,dNTP, Taq DNA polymerase,primers and template,were optimized in this study by orthogonal design in five factors four levels respectively. 【RESULTS】The results showed that the optimum SRAP reaction system included Mg2+ 2.5mmol/L,dNTP 2mmol/L, Taq DNApolymerase 0.5U,primer 1.2mmol/L and DNA template 90 ng in the total 25μL reaction system.【CONCLUSION】Lay the foundation for the construction of fingerprints.