The invention relates to an organic light emitting display device and a manufacturing method thereof. The organic light emitting display device comprises a first substrate, a low-temperature polycrystalline silicon layer, an organic electroluminescence device and a second substrate; the low-temperature polycrystalline silicon layer is formed on the first substrate, and the organic electroluminescence device is arranged on the low-temperature polycrystalline silicon layer; the second substrate has a packaging area, a part of the packaging area is provided with a shield layer, and the packagingarea is provided with a packaging layer, the shield layer and the packaging layer are overlapped, the packaging layer is arranged on the outer side of the low-temperature polycrystalline silicon layerand the organic electroluminescence device, and the second substrate is connected with the first substrate hermetically through the packaging layer. Since the second substrate is provided with the shield layer, energy from laser to secondary sintering of packaging glass materials is reduced, the packaging layer formed by secondary sintering and other part of packaging layer can be sintered underthe same or near laser energy, so that the packaging layer formed by secondary sintering and the other part of packaging layer have the same characteristics, and further, the organic light emitting device has better packaging effect.