PROBLEM TO BE SOLVED: To provide a liquid spray device that is superior in self-propelling performance in a small house, by holding the horizontality of a boom nozzle, reducing the fluttering and improving the lifting operability, and also by compactifying a device body, and its conveying cart, and further to provide a liquid spray system that uses the liquid spray device.SOLUTION: A liquid spray device of the present invention is provided for spraying hot water or chemicals in a house for plant growth, and includes a boom nozzle, means for making the liquid spray device travel by itself, and lifting means for lifting the boom nozzle. The lifting means is disposed between the boom nozzle and the means for making it travel by itself, and is directly connected with the means for making it travel by itself. The lifting means comprises: a base coming into abutment with the central part of the boom nozzle and connected therewith at the spraying nozzle side of the boom nozzle or at the opposite side； struts provided around the base and stretchable in the vertical direction； and a lifting drive unit abutted and connected with the base, and disposed in a space surrounded by the struts.【課題】ブームノズルの水平性の保持、バタツキの低減及び昇降操作性の向上を図るとともに、装置本体をコンパクトにすることによって狭いハウス内でも自走性能に優れた液体散布装置とその運搬台車及び該液体散布装置を用いる液体散布システムを提供する。【解決手段】本発明は植物育成用ハウス内で温湯又は薬剤を散布する液体散布装置であって、ブームノズルと、前記液体散布装置を自走させる手段と、前記ブームノズルを昇降するための昇降手段とを有し、前記昇降手段は、前記ブームノズルと前記自走させる手段との間に配置して前記自走させる手段と直結されており、前記ブームノズルの散布ノズル側若しくはその反対側で前記ブームノズルの中央部に当接して接続する基台と、該基台の周囲に設けられた上下方向に伸縮可能な支柱と、前記基台に当設して接続し、前記支柱が囲む空間内に配置される昇降駆動装置とからなる。【選択図】図１
