The invention discloses an automatic positioning and searching system of urban public parking spots and a using method thereof. The automatic positioning and searching system comprises parking spot sensors, a line concentrator, a data center, a terminal processor and mobile clients; and the parking spot sensors are collected and connected through lines and are provided with the line concentrator, the line concentrator is connected through a line and is provided with the data center, the data center is composed of a map storage unit, an alarm unit and a wireless connection unit, the terminal processor is disposed at a service center, mobile clients are installed in users' intelligent mobile phones, and each mobile client comprises a network connection unit, a registration unit and a mobile positioning unit. After registration connection is carried out through one mobile client, a condition of parking spots near a destination can be obtained, so a parking place can be selected intelligently, optimization configuration of social resources is achieved, an urban parking pressure is reduced, and shutting for road traffic is effectively performed.