The present invention relates to an automatic watering device, method and system. The automatic watering device comprises a housing. One end of the housing is provided with a water inlet that can be connected to an external water supply system. The other end of the housing is provided with a water outlet. The water inlet is provided with a first adapter. The water outlet is provided with a second adapter. The second adapter is detachably connected to a water outlet component. The automatic watering device also comprises: a control device； and a switch component and a radiofrequency identification component connected to the control device. The control device is installed inside the housing. The radiofrequency identification component is installed on the housing. The radiofrequency identification component is used to read flower pot data stored on a radiofrequency identification tag of a flower pot. The water inlet and the water outlet form therebetween a watering passage for allowing water from the external water supply system to flow inside the automatic watering device. The watering passage is provided with a water flow meter for obtaining water flow data for the watering passage. The watering passage is also provided with the switch component for performing an open or close operation to control water flow inside the watering passage. The water outlet component is for discharging, from inside the automatic watering device, the water flow between the switch component and the water outlet. The present invention can achieve intelligent control of a flower pot watering amount, is easy to use, and reduces manual labor.La présente invention concerne un dispositif, un procédé et un système d'arrosage automatique. Le dispositif d'arrosage automatique comprend un boîtier. Une extrémité du boîtier est dotée d'une entrée d'eau qui peut être reliée à un système d'alimentation en eau externe. L'autre extrémité du boîtier est dotée d'une sortie d'eau. L'entrée d'eau est dotée d'
