Abstract: A method for detecting a three-dimensional object in a two-dimensional image includes: inputting the two-dimensional image into an object detection model, and obtaining a resulting detection depth dataset; obtaining, based on the detection depth dataset, coordinate sets of a number of points-of-interest each associated with a to-be-detected object in a 3D camera centered coordinate system; and converting the coordinate sets of the number of points-of-interest in the 3D camera centered coordinate system into a number of coordinate sets in a 3D global coordinate system. Embodiments of this disclosure may be utilized in the field of self-driving cars with roadside traffic cameras.