Sun Sensor is a kind of popular photoelectric sensors in satellite attitude control system. It is very important to have a large field of view for the sun sensor during the course of the sun acquisition of the satellite working in the emergence mode. A ladder-shaped narrow slit sun sensor is presented, which has a very large field of view (157°) and is suitable for the application with the large attitude angle (≤175°). The design of ladder-shaped narrow slit can decrease the sensor's output pulse widths which vary largely with the attitude angle, and be convenient for the correlative circuit design. The onboard experiment validates the practicability of the presented sun sensor.