With the development of automatic rendezvous and docking missions from Earth orbit to deep space, new sensors are needed to perceive precise ranging and bearing information of the target at a longer distance. A new type of laser line-of-sight (LOS) deviation measuring and ranging system is developed, which is characterized by an operational range of 0.5 m to 20 km with a precision of 0.4 m (far) and 0.025 m (near), and a scanning range of up to 120∘×145∘ with an precision of LOS angle up to 0.025°. In addition, gaze-tracking capability enables the system to capture and track high-speed targets. The scheme of the designed system is presented in detail, including optical path design, scanning strategy for tracking, ranging signal processing, and LOS measurement. Meanwhile, the performance of the designed system is verified by extensive indoor and outdoor experiments, including ground simulated rendezvous and docking experiments from about 20 km to 0.5 m.