The present disclosure provides an object detection method, an object detection device, and a storage medium. In the present disclosure, with respect to each contour existing in an image to be detected, a contour diameter is calculated; a shape of the contour is determined based on side lengths of the circumscribed rectangular frame of each contour and the contour diameter; and an object in the image to be detected and parameter information of the object is determined based on the shape of each contour, thereby quickly and accurately detecting the shape of the object and reducing the labor cost and time of detection due to the low complexity of the detection.