The drip irrigation device of the present invention is formed in a plate shape elongated in the longitudinal direction of a flow pipe having a bottom surface joined to the inner peripheral surface of the flow pipe and an upper surface opposite to the bottom surface, and is disposed on the upper surface. An inflow portion for allowing the irrigation liquid in the pipe to flow into the flow path, a discharge amount control section for controlling the discharge amount of the irrigation liquid discharged from the discharge port via the flow path, and one end in the longitudinal direction on the upper surface And a first groove portion formed in a shape in which the groove width and the groove depth gradually decrease toward the other end side.本発明の点滴灌漑装置は、流通管の内周面に接合される底面およびこれの反対側の上面を有する流通管の長手方向に長尺な板状に形成され、上面上に配置され、流通管内の灌漑用液体を流路内に流入させる流入部と、流路を経て吐出口から吐出される灌漑用液体の吐出量を制御する吐出量制御部と、上面上に、前記長手方向における一端から他端側に亘って凹入形成され、前記他端側に向かうにしたがって溝幅および溝深さが漸減するような形状に形成された第１溝部とを有する。
