An image sensor applied to a camera assembly including a lens assembly, the image sensor includes: a substrate including a curved photosensitive surface facing the lens assembly and arranged at a focus of ambient light transmitted from the lens assembly; and a plurality of pixels on the photosensitive surface and arranged in an array including a plurality of rows and a plurality of columns, and each of the plurality of row extending along a first direction X and each of the plurality of columns extending along a second direction Y perpendicular to the first direction X. A spacing between geometric centers of each two adjacent pixels of the plurality of pixels gradually decreases from a center to an edge of the substrate. A camera assembly is also provided.