The invention provides a positioning system of positioning a wireless communication apparatus. The positioning system transmits and receives positioning signals which have different frequency bands and generates corresponding positioning values according to the positioning signals. The positioning system then judges and selects positioning values which have less error from the generated positioning values, and calculates an average value of the selected positioning values. Therefore, positioning of the wireless communication apparatus will be more precise. Furthermore, if the positioning system is implemented in a radio-wave-based wireless communication environment, the N positioning signals can be polarized in a linear polarization way, a left-handed circular polarization way or a right-handed circular polarization way, so as to reduce the environmental impact to enhance precision of the positioning.