Abstract A zirconium oxide (ZrO 2) thin film was prepared using oxygen radio frequency (RF) inductively coupled plasma (ICP) sputtering of the zirconium target with a negative bias in order to protect china and porcelain from metallic contamination and/or to keep their water-repellent nature. The film prepared by dry process is proposed in order to solve environmental problems caused by an existing wet process. The stoichiometric ZrO 2 film is prepared in an amorphous state. It was found that the original substrate, china and porcelain, had a water-contact angle of about 30°, while the prepared film showed a water-repellent nature with an angle of about 90°. The water contact angle of the prepared film was similar to that of the conventional sol–gel method. From these results, this dry process using RF plasma sputtering was certified to be effective in modifying the surface state of china and porcelain.