In this study, nine representative oat varieties (Gao 719, Dingju 6, Dingju 12, Ba 6, Ba 14, Ba 17, Zhang Yu 9, 9754, 9837, hereinafter referred to as G719, DY6, DY12, HBY6, HBY14, HBY17, HZY9, 9754, 9837) were selected from Hebei, Gansu and Jilin regions, and the important functional factor, β-glucan (OβG), was used as the key index. The nutritional composition of oat raw materials and the differences in the properties of OβG extracted from them were discussed. The results revealed significant differences (P<0.05) in starch, protein, fat, and OβG content among the oat varieties. The OβG content ranged from 3.15% (HZY9) to 5.89% (HBY17). The comparison of the structural characteristics of OβG extracted from different oat varieties shows that the relative molecular mass (Mw) of OβG ranges from 4.79×105 g/mol to 8.36×105 g/mol, with the maximum value of HBY17 being 1.75 times that of HBY6. In terms of rheological properties, HBY17 exhibits the highest apparent viscosity, while HBY6 shows the lowest, with a difference of 4.35 times at a shear rate of 0.11/s. The differences in OβG absorption peaks were confirmed by Fourier-transform infrared spectroscopy (FTIR) and small-angle X-ray scattering (SAXS). OβG derived from HBY17 shows the strongest absorption peaks at 1 075 cm–1 and 0.102 nm–1, reflecting the high aggregation degree of this polysaccharide molecule. As a variety with high OβG content and a high degree of polymerization, HBY17 may have greater potential for the development of functional oat products in the future.