ZrNx films were deposited by radiofrequency reactive magnetron sputtering technique in nitrogen and water vapour atmosphere varying the working temperature from room temperature to 600 °C. The films' physical properties were investigated using X-ray diffraction, Secondary Ion Mass Spectroscopy, Atomic Force Microscopy and Transmission Electron Microscopy. It was found that the increase of temperature caused a decrease in the oxygen incorporation and a transition from cubic phase of Zr2ON2 to ZrN one. The formation of nanosized crystalline particles dispersed in the amorphous matrix was observed.