A flat panel display device with an oxide thin film transistor and a fabricating method thereof are disclosed. The fabricating method of the flat panel display device includes: preparing a substrate defined into a pixel region and a pad contact region; forming a gate electrode and a link line; forming a pixel electrode within the pixel region; forming an oxide layer on the substrate provided with the pixel electrode; forming a passivation layer on the substrate and performing a formation process of contact holes to expose the link line; and forming a second transparent conductive material film on the substrate.