An organic EL display device includes a thin film transistor substrate that has a circuit layer, a passivation layer, a lower electrode formed in each pixel in a display region, an organic material layer that is in contact with the lower electrode, an upper electrode that covers the organic material layer, and a sealing layer that entirely covers the base material. The thin film transistor substrate has the display region, and a moisture blocking region that surrounds the display region. On the moisture blocking region, the circuit layer, the passivation layer, the moisture blocking layer, and the sealing layer are laminated in this order. A composition of the moisture blocking layer is different from a composition of the sealing layer.