An image sharing method and a terminal device is provided. The image sharing method of the present invention includes: obtaining an image selected from a gallery by a user, and using the image as a to-be-shared image, where a quantity of the to-be-shared images is greater than a single-time maximum shareable-photo quantity allowed by a target sharing platform; and performing synthesis processing on at least two images of the to-be-shared images to obtain a processed to-be-shared image, where a quantity of the processed to-be-shared images is less than or equal to the single-time maximum shareable-photo quantity allowed by the target sharing platform.