The invention provides a monocular vehicle 3D target pose estimation method, system and terminal and a storage medium. The method includes: S01, establishing a basic network model; S02, acquiring a captured image, acquiring a labeled contour of an object to be labeled from the captured image, acquiring coordinate data of each vertex of the labeled contour, and taking plane coordinate data of eachvertex of the labeled contour as an input of a training basic network model to train the basic network model; and S03, inputting an image to be detected into the basic network model, and outputting the 3D labeled result of the captured image. The method establishes a fast detection based CNN network model, two-dimensional vehicle target detection and three-dimensional vehicle pose estimation are carried out, and the pose of the target is estimated while the target is detected. The SSD algorithm is extended to cover the whole 3D pose space, and only the synthetic model data is trained; and onlythe traditional vision sensor is needed, the hardware cost is very low, and the performance-price ratio is high.