Selection of primary trisomics of the cabbage (Brassica oleracea var.capitata L) forms an important basis for gene chromosome mapping and for other genetic studies. The cabbage self-fertilization line - 9601 was used as material, using the root-tip cell chromosome number and pollen mother cell chromosome number identification and karyotype analysis to select the primary trisomics from the progenies of 3x × 2x in the cabbage. Many aneuploid plants with one or two extra chromosomes were obtained and a set of primary trisomics (Tri-1, Tri-2, Tri-3, Tri-4, Tri-5, Tri-6, Tri-7, Tri-8, and Tri-9, in which the Tri- 1 and Tri-4 were from 2n + 2 plants and others from 2n + 1 plants) was acquired from these plants. Each trisomic exhibited some unique features, such as plant height, plant type, leaf type, size of flower bud, and inflorescence.The triploid crossing by the diploid is a convenient and effective way to select trisomics in the cabbage.