Abstract: The defects in the coatings on key aerospace components made of titanium alloy have always been a research focus. To solve the serious defects in chromium coatings caused by the sandblasting of titanium alloy base metal, the effect of sandblasting parameters on the defects of titanium alloy coating was studied. The causes for coating defects were analyzed by magnetic particle detection, metallographic microscope, energy spectrometer and scanning electron microscope, and the sandblasting parameters were recommended. The experimental results show that the white corundum sand will be embedded onto the surface of the titanium alloy base material when the titanium alloy is sandblasted, resulting in poor binding between the coating and the base material and then the coating cracking. Using 100-mesh (150 μm) white corundum sand and 0.4 MPa blasting pressure can effectively improve the presence of residual white corundum sand on the base material surface. and provide guidance for the selection of sandblasting parameters in order to obtain high-quality titanium alloy coatings.