Abstract: A method for breeding a new germplasm of clubroot-resistant orange-heading Chinese cabbage includes: (1) obtaining F1 by hybridizing orange-heading Chinese cabbage as a female parent and clubroot-resistant Chinese cabbage as a male parent, obtaining F2 by selfing F1 individual plants, planting F2 populations, and extracting DNA from the individual plants of F2; (2) observing horticultural traits of F2, and performing observation and statistics of head color phenotypic traits through cutting head; (3) performing PCR amplification with DNA of F2 using a dominant orange gene marker Br530 and a clubroot-resistant marker SC2930-T/SC2930Q, and identifying a genotype of the individual plants; (4) performing a comprehensive evaluation according to the results of marker detection and the observation of horticultural traits, selecting double-site homozygous clubroot-resistant orange-heading Chinese cabbage plants, and selfing the individual plants for 2 consecutive generations; and (5) obtaining a new germplasm of club