Abstract: The microstructural evolution and mechanical properties of Hastelloy C-276 alloy sheet with different deformations were investigated using the optical microscope (OM), electron back-scattered diffraction (EBSD), and tensile test. The results show that dislocation pile-ups and local strain concentration preferentially appear at grain boundaries under the deformation less than 14%. When deformation is in the range of 14~30%, a great quantity of dislocation was produced which located at twin boundaries and within grains, and the dislocation slip led to high strain concentration within grains. When deformation degree increasing from 0 to 30%, the strain concentration degree of grain boundaries increases at first then decreases, and reaches the maximum at 14%. The Ludwigson model can describe the true stress-true strain curves by the regression fitting. With the deformation degree increasing, the degree of work-hardening improved while the work-hardening rate decreased, and the critical strain of single slip transforming to multiple slip decreased.