The invention provides a compensation correction method of a flat panel detector image lag. The compensation correction method comprises the following steps of generating a lag data sheet and storingthe data sheet in a flat panel detector or detector software; obtaining a current bright field image and a dark filed image; enabling a lag signal of each pixel in the dark field image to be corresponding to the lag data sheet, and finding out a lag value of the lag signal of each pixel corresponding to the lag data sheet, and a moment corresponding to the lag value; enabling the moment corresponding to the lag value to be added with the time interval of the collection time between the current bright field image and the dark field image to obtain a new moment, finding a lag value correspondingto the new moment from the lag data sheet, and generating a current image evaluation lag template matrix; and enabling the lag template matrix to be subtracted from the current bright field image toperform lag compensation correction. The compensation correction method of the flat panel detector image lag disclosed in the invention can be used for solving the complex lag problems, and is wide inapplicable range, and suitable for a noncrystalline silicon detector and amorphous selenium, CMOS and other semiconductor detectors.