The invention discloses a large-scale marine pipeline initial point recognition and location method and system based on CCD. The method and system comprise the following steps that: (1) the position of a welding line is preliminary located, wherein a CCD industrial digital camera collects the images of the welding line, a main control computer calculates the real-time change of line pixel deviation between the center of a welding gun and the center of the welding line, and a welding robot is located above the welding line preliminary; (2) pixel coordinates of an initial point are extracted, wherein one welding spot of positioned welding is recognized, a dislodgement machine drives a pipeline to move rotatably, images are collected in real-time, picture processing is conducted to a rectangular area-of-interest containing the welding gun, if the welding spot is detected, the dislodgement machine stops rotating, and the pixel coordinates of the barycenter of the welding spot are extracted; (3) the initial point is located, wherein the welding robot moves horizontally by a short distance in the Y direction of a basal coordinate system, the images of the welding line are collected, the pixel coordinates of the barycenter of the welding spot are extracted again, the three-dimensional coordinates of the initial point are calculated by the utilization of stereoscopic vision, and the welding robot is located to the initial point.