Liquid dosage device comprises a cylindrical body filled with a liquid, having a distal end side needle tip, provided at the distal end of the tubular body, the tubular body and communicable needle tube, can slide in the tubular body and a gasket, an operating member for performing a pressing operation to press against the gasket in the distal direction to eject the liquid from the needle tube, a first position covering the restricting capable regulating member pressed, the distal end side needle point, the distal end and a second cover member movable to a position where Gawahari destination is exposed, the regulating member, projections formed to protrude, the operation member is formed with a groove protrusion is inserted , the groove has a longitudinal groove formed along the operation direction in the same direction at the time of pressing operation, communicates with the longitudinal groove, and a transverse groove formed along a direction perpendicular to the operating direction, the cover member there when in the first position, projections located in lateral grooves, to regulate the pressing operation, when the cover member is moved from the first position to the second position, projections in conjunction with the movement There moved longitudinally groove from the lateral groove, thereby pressing operation can be performed.液体投与具は、液体が充填された筒体と、先端側針先を有し、筒体の先端側に設けられ、筒体と連通可能な針管と、筒体内で摺動し得るガスケットと、ガスケットを先端方向に向かって押圧して液体を針管から吐出させる押圧操作を行なう操作部材と、押圧操作を規制可能な規制部材と、先端側針先を覆う第1の位置と、先端側針先が露出する第2の位置とに移動可能なカバー部材とを備え、規制部材には、突部が突出形成され、操作部材には、突部が挿入される溝が形成されており、溝は、押圧操作時の操作方向と同方向に沿って形成された縦溝と、縦溝に連通し、操作方向に対し垂直な方向に沿って形成された横溝とを有し、カバー部材が第1の位置にあるときに、突部が横溝に位置して、押圧操作を規制し、カバー部材が第1の位置から第2の位置に移動した際、その移動に連動して突部が横溝から縦溝に移動し、これにより、押圧操作が可能となる。
