An organic light emitting display device which prevents deterioration of an organic light emitting diode (OLED), the organic light emitting display device includes a first substrate including a display unit that includes at least one organic light emitting diode (OLED), a second substrate facing the first substrate and bonded to the first substrate, a sealant arranged surrounding the display unit and bonding the first substrate to the second substrate, a dam portion arranged between the display unit and the sealant and surrounding a periphery of the display unit and including a plurality of magnetic particles and a filling material arranged within an inner space of the dam portion and between the first and second substrates and including a plurality of magnetic particles.