In this article, we focus on how to fuse two systems between SLAM and UAV. The main contribution is that using the UAV attitude controller provides a reliable initial value for the SLAM system, which makes the direct method of SLAM more quickly and effective converge. The UAV position controller increases the stability by receiving the exact local information from SLAM. That allows two independent systems to promote each other. Finally, we design relevant experiments to verify the feasibility of this method. We verify the idea with a good response to the rapid rotation of the camera.