The present disclosure provides a thin film transistor array. In an exemplary embodiment, the thin film transistor array includes: a substrate; a gate line including a gate pad and disposed on the substrate; a gate insulating layer disposed on the gate line and the gate pad; a data line including a data pad and disposed on the gate insulating layer; a first passivation layer disposed on the data line; a first electrode disposed on the first passivation layer; a second passivation layer disposed on the first electrode; and a second electrode disposed on the second passivation layer. The gate pad is exposed through a first contact hole, and the gate insulating layer, the first passivation layer, and the second passivation layer include at least a portion of the first contact hole.