Embodiments of this application provide an image transmission method and apparatus. The method includes: converting a first high-resolution image into a first low-resolution image, where first resolution of the first high-resolution image is higher than second resolution of the first low-resolution image; encoding the first low-resolution image to obtain a first bitstream; obtaining a second high-resolution image, where third resolution of the second high-resolution image is higher than the second resolution, and the second high-resolution image includes high-frequency information of the first high-resolution image and excludes low-frequency information of the first high-resolution image; obtaining an image residual between the first high-resolution image and the second high-resolution image, where the image residual is used to reflect the low-frequency information of the first high-resolution image; encoding the image residual to obtain a second bitstream; and sending the first bitstream and the second bitstream.