Provided is a depth image unfolding apparatus and method that may remove a depth fold from a depth image to restore a three-dimensional (3D) image. The depth image unfolding apparatus may include an input unit to receive inputted multiple depth images with respect to the same scene, the multiple depth images being photographed based on different modulation frequencies of a fixed photographing device, a depth fold estimator to estimate a number of depth folds based on a distance between multiple three-dimensional (3D) points of multiple pixels indicating the same location of the scene in the multiple depth images, and an output unit to output the multiple depth images from which depth folds are removed based on the estimated number of depth folds.