A light emitting display device where a pixel circuit detecting a threshold voltage of a driving transistor in each of a plurality of subpixels is arranged in a matrix, includes: a threshold voltage estimating part generating a threshold voltage estimation value by estimating the threshold voltage of the driving transistor through a data counting method; a reference voltage modifying part generating a reference voltage modification value by modifying a reference voltage used for detecting the threshold voltage based on the threshold voltage estimation value; an image data voltage modifying part generating an image data voltage modification value by adding a threshold voltage detection value to a data voltage corresponding to an image data; and an accumulated deterioration calculating part calculating an accumulated deterioration by accumulating a deterioration data of a function of the data voltage.