Abstract: In order to investigate the growth characteristics, production performance, nutritional value and cytogenetic characteristics of the four new strains of sorghum-sudangrass SLCN-11, SLCN-12, SLCN-13, SLCN-14, the main agronomic characteristics and chromosome configuration, such as the growth rate, fertility, photosynthetic performance, fresh and seed yields, hydrocyanic acid content, nutrients and so on, were analyzed. The four new strains grew fast and were tall, tillering ability was strong, the growth period was 130-138 d, the ear type was in middle of their parents, pollen fertility rate was above 96%, seed setting rate was 72.11%-73.34%, The chromosome pairing behavior at PMC M I was regular (2n=2x=20=10Ⅱ). The four new strains had stronger photosynthetic capacity. Their fresh and seed yields were high. The fresh and seed yields of strain SLCN-11 were the highest. The hydrocyanic acid content of the four new strains were low, the hydrocyanic acid content in fresh sorghum-sudangrass was only 5.80-10.43 mg/kg when the plant height was about 100 cm, which was safe for feeding animals. The ratio of stem to leave was low and the nutritional value was high. At the jointing stage, the crude protein content of four new strains was 14.67%-16.31%, the crude fiber content was 24.31%-24.72%, and was rich in crude fat, nitrogen free extract, calcium, phosphorus and amino acids.