A transistor array panel according to an exemplary embodiment includes a substrate, and a first transistor and a second transistor positioned on the substrate. Each of the first transistor and the second transistor includes: a first electrode; a second electrode overlapping the first electrode; a spacing member positioned between the first electrode and the second electrode; a semiconductor layer extending along a side wall of the spacing member; and a gate electrode overlapping the semiconductor layer. A thickness of the spacing member of the first transistor is larger than a thickness of the spacing member of the second transistor.