Abstract: Dynamic tracking methods for an in-vivo three-dimensional key point and an in-vivo three-dimensional curve can include mapping a first local region to a first local point cloud and mapping a second local region to a second local point cloud according to a mapping relation between an endoscopic image and the point clouds; determining a first three-dimensional key point of a first two-dimensional key point on the first local point cloud, and acquiring a second three-dimensional key point on the second local point cloud through a coordinate transformation; and mapping the second three-dimensional key point back to the second local region, so as to acquire a second two-dimensional key point from a next image; and acquiring two-dimensional coordinates of a tracked key point by minimizing a preset optimization function in combination with an initial two-dimensional key point, and finally acquiring corresponding three-dimensional coordinates.