The present invention discloses a method and an apparatus for detecting a convex polygon image block, and a device. The method includes: acquiring an image collected by an image sensor; acquiring a corner set, where the corner set includes a corner in the image, and the corner is an intersection point at which any two straight line sides that are not parallel to each other in the image intersect; and detecting a convex polygon image block in the image according to the corner set, where a shape of the convex polygon image block is a preset shape and a similarity between the convex polygon image block and a preset image block exceeds a preset first threshold. The apparatus includes: a first acquiring module, a second acquiring module, and a detecting module. In the present invention, the convex polygon image block can be detected from the image.