The mechanical properties of Avena sativa stalks are the basis for Avena sativa growth, harvest, threshing, cleaning process and equipment design, which also contribute to deep processing and modification of polymer resources. The physical and chemical components and microstructure characteristics of Avena sativa stalks in different internodes were investigated. The shear and compression properties of Avena sativa stalks under static loading conditions were analyzed, the results of which presented that the moisture content significantly affected the shear and compression mechanical parameters (p<0.05). The dynamic mechanical properties of Avena sativa stalks with different moisture contents were studied by dynamic mechanical analyzer (DMA). The results presented that the Avena sativa stalks showed viscoelastic properties. With the increase of moisture content, the elasticity of Avena sativa stalk was decreased while the viscosity was increased. When the moisture content was 15.14%, the minimum strain was 0.0052. The creep-recovery and stress relaxation curves obtained by the experiment were introduced into the Burgers model and the five-element generalized Maxwell model respectively, and the determination coefficients (R2) were all above 0.99. As the moisture content was increased, the elastic modulus (E1) and the equilibrium elastic modulus (Ec) were decreased, and the stress relaxation time (τK) was increased. The structural analysis and mechanical properties of Avena sativa stalks can provide experimental basis for the development of Avena sativa stalk collection and processing machinery.