An automatic pot culture watering device comprises a shell, a joint, a plug, a linking rod, and a float. The shell has a bottom wall, a top wall, a surrounding wall circumferentially connected between the periphery of the bottom wall and the top wall, and a water replenishing container defined by the bottom wall, the top wall and the surrounding wall together. The surrounding wall has at least one water inlet communicating the water replenishing container to the outside and a lock hole. The surrounding wall has an air intake passage having one end provided with an inner opening located on top of the surrounding wall and communicated with the water replenishing space, and another end provided with an outer opening located at the bottom of the surrounding wall and communicated to the outside. The joint comprises an outer connection portion, an inner connection portion, and a locking portion connected between the outer connection portion and the inner connection portion. The outer connection portion is penetrated through the shell from the lock hole. The locking portion has a water inlet. The plug is disposed in the inner connection portion of the joint and has several water discharge grooves. The linking rod has a rod body comprising a pushing portion, a connecting portion, and a pivoting portion connected between the pushing portion and the connecting portion, in which the pivoting portion is pivoted with the inner connection portion of the joint and the float is connected to the connecting portion of the linking rod. Thus, the present invention may achieve the effect of automatic watering in suitable timing with suitable amount.一種盆栽自動澆水裝置，包含有一殼體、一接頭、一塞柱、一連動桿及一浮筒；殼體具有一底壁、一頂壁、一環狀連接於底壁與頂壁周緣間之周壁及一由底壁、頂壁與周壁共同圍繞出之補水容室，周壁具有至少一連通補水容室至外界之進水孔與鎖孔，周壁具有一進氣通道，進氣通道一端具有一內部開口，內部開口係位於周壁之頂部並連通補水空間，進氣通道另一端具有一外部開口，外部開口係位於周壁之底部並連通至外界，接頭具有一外接部、一內接部及一連接於外接部與內接部間之鎖接部，外接部係自鎖孔穿出於殼體外，鎖接部具有一入水孔，塞柱置於接頭之內接部內，具有若干之出水槽，連動桿具有一桿身，桿身具有一推抵部、一連接部及一連接於推抵部與連接部間之樞接部，樞接部與接頭之內接部樞接，浮筒與連動桿之連接部連接；藉以達到適時、適量自動澆水之
