An organic light emitting display, including a first data line extending along a first direction, a second data line extending along the first direction and disposed parallel to the first data line, a first scan line extending along a second direction perpendicular to the first direction, a first pixel connected to the first data line and the first scan line, a second pixel connected to the second data line and the first scan line, a first constant current source connected to the first data line, a second constant current source connected to the second data line, and a temperature information generation unit comprising a first input port connected to the first data line and a second input port connected to the second data line.