In this work the main effective parameters on the electrical resistivity of copper nitride thin films are investigated. Copper nitride thin films were successfully deposited on glass substrates by reactive dc magnetron sputtering at room temperature but different sputtering time. Working gas was a mixture of argon and nitrogen with equal amounts. The effect of deposition time on the structural, optical and electrical properties of deposited films was investigated. X-ray diffraction measurements show different lattice orientation in the structure of deposited films. By increasing the time of sputtering an orientation change from (100) to (111) can be observed in the films. Film morphology of samples is not changed with the sputtering time. The optical transmittance of deposited films decreases with increasing the deposition time. Results confirm that when the amount of nitrogen in working gas is 50%, we have more (100) planes in the structure of the deposited films, leads to higher resistivity of the films.