An organic light emitting diode display and a manufacturing method thereof are provided. The organic light emitting diode display includes a first substrate, a second substrate, a plurality of organic light emitting diodes, and a frit layer. The organic light emitting diodes are disposed on the first substrate, and the frit layer adheres the first substrate and the second substrate to each other. The frit layer includes a first porous region having pores, a second porous region having pores, and a third porous region having pores. The number of the pores of the first porous region with a diameter of larger than or equal to 4 μm and smaller than or equal to 15 μm is greater than the number of the pores of the second porous region with the above-mentioned diameter range.