The invention provides a specific primer, a probe, a kit and a method for detecting barley component. A large number of primers are designed based on FDH, GLU2a, RBCL, ACPS and UDPg genes of barley, and primers and probes with species specificity are screened out through a large number of primer screening researches. When the primers and the probes are used for detecting barley component in a sample to be detected, barley and other species adulterants can be accurately separated, the absolute detection sensitivity reaches 0.2 copies / microliter, the relative sensitivity can reach 0.5%, and theidentification result is accurate, stable and reliable.