A substrate structure including a flexible substrate, a gate line, a gate, an inorganic insulation layer, a semiconductor layer, a source, a drain, an inorganic passivation layer and an organic insulation layer is provided. The gate is electrically connected to the gate line. The inorganic insulation layer covers the gate and exposes a portion of the flexible substrate. The semiconductor layer is disposed on the inorganic insulation layer and disposed corresponding to the gate. The source and the drain extend from the inorganic insulation layer to the semiconductor layer and expose a portion of the semiconductor layer. The inorganic passivation layer covers portions of the source and the drain and directly contacts to the semiconductor layer exposed by the source and the drain. The organic insulation layer covers the source, the drain, the inorganic passivation layer and the flexible substrate exposed by the inorganic insulation layer.