The invention discloses a Ni-Zn-N film barrier layer and a preparation method thereof. In percent by mass, the Ni-Zn-N film barrier layer comprises 60-85% of Ni-Zn alloy and 15-40% of Zn3N2 and Ni3N2as the remaining components. Compared with the prior art, the Ni-Zn-N film barrier layer has the advantage of significant improvement on stability; the Ni-Zn-N film barrier layer is insusceptible to temperature change, has excellent moisture resistance and is insusceptible to moisture vapor erosion; the service life of a prepared electrode is significantly longer than that of the conventional electrode; the film thickness of the barrier layer is smaller than 70nm, and is far smaller than that of the conventional barrier layer; the conductive property of the prepared electrode is equivalent tothat of the conventional Ag electrode; the preparation method is simple and easy to implement; the preparation cost is low.