Tensile experiments were conducted at different temperatures for the Haynes 230 nickel-based alloy, and the microscopic mechanism of the tensile deformation behavior at high temperatures was investigated using Electron Backscattered Diffraction (EBSD) technique.It is shown that Haynes materials have a high resistance to plastic deformation until 800℃. At 650℃, the materials show a significant dynamic strain aging (DSA) phenomenon, and the DSA effect is similar at 700℃ and 800℃, and the DSA effect is weakest at 760℃.The strengthening effect of DSA effect makes the alloy still maintain high strength at 650℃, and the tensile strength at 800℃ does not decrease much compared with that at 760℃.The EBSD results show that a large number of deformed twins appear near the fracture at room temperature, and the grain orientation is dominated by <111>; the <111> orientation of the tissue near the fracture is more obvious at 650℃, and the grain boundaries are bent and deformed, which increases the resistance to dislocation movement; with the increase of temperature, dynamic recrystallization grains appear in the intergranular and intracrystalline areas near the fracture.