Plasma sprayed coatings of yttrium oxide, exhibiting good adhesion and thermal shock resistance, were developed on various substrates using thermal spray grade yttrium oxide powder developed in our laboratory. Numerical simulation of particle behaviour in the thermal plasma jet was combined with experimental method to develop the coatings. Phase structure and microstructural characterisation of the deposits were evaluated by X-ray diffraction, Raman spectroscopy and scanning electron microscopy. Deposition efficiencies and adhesion strength of the coatings deposited at different power levels could be well explained with the predictions provided by the model. The process was optimised using deposition efficiency as the response parameter.