This study attempted to manufacture an Y 2 O 3 ceramic coating layer on a ceramic (AlN) substrate using aerosol deposition (AD) and investigated its macroscopic properties.Pure Y 2 O 3 powder with a polygonal shape and average size of 5.0 μm was used as initial feedstock.Using aerosol deposition with suitable process conditions, an Y 2 O 3 coating layer was successfully fabricated on aluminum nitride (AIN).The thickness of the manufactured coating layer was approximately 10 mm.The coating layer consisted of Y 2 O 3 phase identical to that in the initial powder, and no additional oxides were identified.In regard to the roughness of the Y 2 O 3 coating layer, the average roughness (R a ) measured 1.32 μm, indicating that the surface roughness was relatively even compared to the initial powder size (5 μm).Mechanical properties of the Y 2 O 3 coating layer were measured using nano indentation equipment, and the indentation modulus of the Y 2 O 3 coating layer fabricated by aerosol deposition measured 136.5 GPa.The interface of the coating layer was observed using TEM, and the deposition mechanism of the Y 2 O 3 coating layer manufactured by aerosol deposition was also discussed.