Various embodiments provide a polygonal region detection method and apparatus, a computer readable storage medium and an electronic device. In those embodiments, a to-be-detected image can be obtained. A plurality of line segments in the image can be calculated based on a line detection algorithm. The plurality of line segments meeting a merging condition can be merged into a line segment. Crosspoints of the pairwise merged line segments can be calculated according to the merged line segments in the image. A polygonal region can be generated with the crosspoints as vertexes of the polygonal region in the image.