There is provided an image processing device and a method that enable partial decoding of 3D data to be performed more easily. Management information of a block as a partial region in a predetermined three-dimensional spatial region including 3D data representing a three-dimensional structure is generated. In addition, a block satisfying a condition specified by a user is selected on the basis of management information of the block as a partial region in a predetermined three-dimensional spatial region including 3D data representing a three-dimensional structure, and coded data of the 3D data within the selected block is decoded. The present disclosure can be applied to, for example, an image processing device, an electronic apparatus, an image processing method, a program, or the like.