The invention provides an SNP molecular marker K_060502 which is tightly linked to a broad-spectrum rice blast resistance gene Pi2. It is detected by the SNP marker that the basic group at the 10432621 site of the 6 chromosome of rice is G or T, and the primer combination of the SNP marker developed based on a KASP technology is Primer X, Primer Y and Primer C. According to the SNP marker,the KASP technology is utilized to perform rapid genotyping on the SNP marker which is tightly linked to the broad-spectrum rice blast resistance gene Pi2, the SNP marker can be applied to commercialmolecular seedling breeding with high, medium or low through-put, the selectivity efficiency of a developed SNP marker phenotype reaches up to 100%, and therefore the broad-spectrum rice blast resistance gene Pi2 can be rapidly and accurately detected in different germ plasm resources of indica rice, japonica rice and the like; the complicated procedures of enzyme digestion, electrophoresis, sequencing and the like are not needed in the detecting process, aerosol contamination is reduced, the use of toxic substances of ethidium bromide EB (ethidium bromide) and the like is reduced, outlook molecular marker auxiliary selection at the early stage of seedling breeding can be conducted to reduce the field planting scale of seedling breeding groups and the seedling breeding cost, and the seedling breeding process is accelerated.