A thin film transistor array panel includes: a substrate, a gate line positioned on the substrate and including a gate electrode, a semiconductor layer positioned on the substrate and including an oxide semiconductor, a data wire layer positioned on the substrate and including a data line crossing the gate line, a source electrode connected to the data line, and a drain electrode facing the source electrode, and a capping layer covering the data wire layer, in which an end of the capping layer is inwardly recessed as compared to an end of the data wire layer.