An organic light emitting display device includes a substrate, a display unit on the substrate, a sealing substrate on the display unit, a sealing member around the display unit and bonding the substrate and the sealing substrate, and a filler inside the sealing member and filling a gap between the substrate and the sealing substrate, wherein the filler is a non-hardening type, and a molecular weight of the filler is from about 100 kg/mol to about 5,000 kg/mol.