An inkjet image forming apparatus and a method of defective nozzle compensation in the inkjet image forming apparatus. The method includes detection of an occurrence and a position of the defective nozzle in a nozzle unit, when the defective nozzle is detected, analyzing image information on image data which are to be printed at a compensated position which is a position printed with the defective nozzle and image data which are to be printed at positions adjacent to the compensated position, and exchanging the image data which are to be printed at the compensated position for image data which are to be printed at one of the adjacent positions according to the analyzed image information and performing printing. Missing dots caused by the defective nozzle are compensated by exchanging image data and performing printing. Accordingly, since the image data are exchanged and printed, it is possible to prevent deterioration in image quality such as a white band which can be easily perceived by a user.