Wireless local area network positioning method, device and system

The invention provides a wireless local area network positioning method, device and system. The method includes: acquiring a field intensity vector, used for marking a position, of a peripheral AP (access point), and using the field intensity vector as a reference vector; at a point to be positioned, receiving WIFI (wireless fidelity) fingerprints from different APs; forming another field intensity vector according to the WIFI fingerprints and using the field intensity vector as a positioning vector; determining the position of the point to be positioned, according to a relation between the positioning vector and the reference vector. According to the scheme, at the point to be positioned, the WIFI fingerprints from the different APs are received, the field intensity vector is formed according to the WIFI fingerprints and is compared to the field intensity vector, originally used for marking the position, of the AP, the specific position of the point to be positioned is determined, and the whole method is sim