The invention relates to a siphon device of a hydroponic planting mechanism. The siphon device includes at least a body tube portion and a siphon tube provided on the body tube portion. The siphon tube has a water suction end and a water outlet end. Inserted into the inside of the main body pipe part, the water outlet end is located outside the main body pipe part； the main body pipe part has an overflow port, the overflow hole is provided with an overflow pipe part, the overflow pipe part is located above the siphon； The siphon part is used to extract the water in the water storage tube to control the level of the water level in the water storage tube, so that the roots of the plants in the planting pot can be changed into a dry, wet and dry state, so that some of the plants can be avoided. The roots of plants that are easily rotten in the pot contact the water in the water storage tube for a long time to cause the occurrence of rotten roots； at the same time, the water supply effect of the lower layer of the planting mechanism provided by the multilayer stack can be improved.本發明乃係一種水耕植栽機構的虹吸管裝置，該虹吸管裝置至少包括有一本體管部、一設於該本體管部上的虹吸管，該虹吸管具有一吸水端及一出水端，該吸水端係插入於該本體管部內側，該出水端係位於該本體管部的外側；該本體管部具溢水口，該溢水口上設有一溢水管部，該溢水管部係位於該虹吸管的上方；藉此該虹吸管部來抽取該蓄水管內的水來控制該蓄水管內水位的高低，而可使該植栽盆內植物的根部處於成乾濕乾濕變更的狀態，從而可避免有些該植栽盆內易爛根的植物根部長時間接觸該蓄水管內的水而產生爛根狀況的發生；同時可提升多層積層設置的植栽機構下層的供水效果。
