ZnO is a wide-bandgap II-IV semiconductor and has a variety of potnetial applications. ZnO exhibits good piezoelectric, photoelectric and optical properties, and is a good candidate for an electroluminescence device. ZnO films have been deposited on (001) sapphire by PLD technique. Nd:YAG pulsed laser was operated at a wavelength of $lambda=355nm$. The ZnO films were deposited at oxygen pressures from base to 500 mTorr. The substrate temperatures was increased from $200^{circ}C; to;700^{circ}C$ films showed strong UV emission by increasing the partial oxygen pressure. We have investigated the relationship between partial oxygen pressure and the intensity of UV emission.