The present invention utilizes the interaction between gravity and penetration to provide well irrigation system, comprising: a well, a water level controller or a water supply bottle. The well has a sink (waterproof container), a water pipe, a holder and a buoy the water level controller has a valve, a tube, a switch valve, and a float the tube is connected to the water pipe the float is located in the tube and is upper than an exit of the tube, the float is connected to the valve and can open or close it the water supply bottle is comprised by a bottle, a movable straight pipe and a height adjuster and inverted in the holder to provide the water by utilizing the principle of pressure control so as to simultaneously use with or substitute for the water level controller. The present invention utilize penetration principle and communicating pipe principle to bury the well in the soil, when the water level is not higher than the opening of the sink, the water can still permeate upward from the bottom when higher, the water pour the outside soil based on connecting pipe principle, the well connect the water level controller to let the water level of the well is equal to the tube’s water level the float will close the valve when the water level is higher than a fixed height, on the contrary, it will open the valve when the water level is lower than the fixed height using the float to control the valve open or close can automatically maintain the water level of the well mechanically to irrigate large area plantation or the plural of potting. The water supply bottle utilize height adjuster to change the straight pipe height in the holder and utilize pressure to auto control, when the water level of the well is lower than the straight pipe, the water supply bottle will provide the water otherwise, it will stop to provide the water so as to irrigate small area plantation or a single potting. And the present invention can adjust the height of the float or the water supply bo
