The invention relates to a single-point self-organization traffic signal controlling method based on a wireless sensor network. The method comprises the following steps: (1) a vehicle node is arranged in the interior of a running vehicle, information collecting nodes are arranged at a road side, and converging nodes are arranged at a crossroad; (2) (Eta, Theta) represents a driveway where the vehicle is in, and every driveway is allocated with a phase p(Eta, Theta) to construct a candidate phase set; (3) traffic data is collected in real time; (4) discrimination is carried out on traffic status of the crossroad, if a non-congestion status is discriminated, an original single time allocation scheme is implemented, but if not, Step (5) is carried out; (5) when waiting time of a certain direction exceeds the upper limit of waiting time, the flow direction with maximum waiting time is selected as a key flow direction which is otherwise determined by calculating pkey (Eta, Theta), green light time is allocated for a planned release phase where the key flow direction is and the wayleave of a green light is granted. The method can provide real-time accurate traffic data detection and realize good controlling result in traffic jams.