Provided are a method and apparatus for encoding or decoding a 360-degree image. According to an image decoding method and apparatus according to an embodiment, an original 360-degree image is reconstructed by acquiring image data from a bitstream, decoding a projection image of a 360-degree image from the image data, converting the projection image into the 360-degree image, acquiring rotation information of the 360-degree image from the bitstream, and rotating the 360-degree image based on the rotation information.