CrNx films were synthesized under graded/constant bias by DC magnetron sputtering. In the present work, the graded bias deposited CrNx films have both (111) and (200) orientations while only (111) orientation in low bias (-20 V) and (200) orientation in high bias (-200 V). Both the magnitude of bias and preferred orientation result in the variation in their surface morphology from pyramidal (loosen) to cellular (dense) structure. The hardness of the graded films is between the low and high constant bias ones. The relationship between the hardness and bias gradient is similar with the relationship of hardness and the content of (200) preferred crystallites, which implies the fine (200) preferred crystallites is an important factor for hardness of graded bias films.