Abstract: A 3D bounding box reconstruction method includes obtaining masks corresponding to a target object in images, obtaining a trajectory direction of the target object according to the masks, generating a target contour according to one of the masks, transforming the target contour into a transformed contour using a transformation matrix, obtaining a first bounding box according to the transformed contour and the trajectory direction, transforming the first bounding box into a second bounding box corresponding to the target contour using the transformation matrix, obtaining first reference points according to the target contour and the second bounding box, transforming the first reference points into second reference points using the transformation matrix, obtaining a third bounding box using the second reference points, transforming the third bounding box into a fourth bounding box using the transformation matrix, and obtaining a 3D bounding box using the second bounding box and the fourth bounding box.