A thin film transistor array panel according to an exemplary embodiment of the present invention includes: an insulation substrate; a thin film transistor disposed on the insulation substrate, wherein the thin film transistor includes a first electrode; a first contact hole pattern having a first width, wherein the first contact hole pattern exposes a portion of the first electrode, and a first contact hole to expose the portion of the first electrode, wherein an inner sidewall of the first contact hole pattern constitutes a first portion of the first contact hole.