The invention discloses a street lamp later night automatic switching control device. The street lamp later night automatic switching control device comprises a time control device and a pedestrian and vehicle detection control device, wherein the pedestrian and vehicle detection control device comprises a detection control circuit and an execution circuit; a coil of the time control device is connected with a power supply; a normally open contact of the time control device is connected with a coil of the execution circuit of the pedestrian and vehicle detection control device in series and then is connected with two ends of the coil of the time control device in parallel; the control end of the detection control circuit is connected with the coil of the execution circuit in series; a normally closed contact of the time control device is connected with a power supply loop of a street lamp; and the normally open contact of the execution circuit is connected with the normally closed contact of the time control device in parallel. After midnight, when pedestrians or vehicles pass through the street lamp, the street lamp automatically lightens; and when no pedestrians or vehicles pass through the street lamp, the street lamp automatically puts out, so that unnecessary consumption of electric energy is reduced, ageing of lamps can be reduced, service life of lamps is prolonged, and engineering cost of the street lamp is saved.