Liquid dosage device 10, and the inner cylinder 1, and the needle tube 2, the gasket 3, and the liquid Q, an outer cylinder 4, and presses the gasket 3 in the distal direction, ejecting the liquid Q from the needle tube 2 a plunger 11 which performs a pressing operation to the ejection completion position that end is, the regulating means 30 capable of regulating the pressing operation on the plunger 11, a first position that covers at least the needle tip 21 of the needle tube 2, group from the first position retracted to the edge direction, a cover member 6 which can move in a second position in which the needle tip 21 is exposed, in the unused state, the cover member 6 is in a first position, the plunger 11, wherein the restricting means 30 is pressed is restricted, when moved from the unused state of the cover member 6 to the second position, the cover member 6 to release the restriction of the pushing operation by the restricting means 30, the pressing operation can be performed.液体投与具10は、内筒1と、針管2と、ガスケット3と、液体Qと、外筒4と、ガスケット3を先端方向に向かって押圧して、液体Qを針管2から吐出させ終わる吐出完了位置まで押圧操作を行なうプランジャ11と、プランジャ11に対する前記押圧操作を規制し得る規制手段30と、針管2の少なくとも針先21を覆う第1の位置と、第1の位置から基端方向に退避して、針先21が露出する第2の位置とに移動可能なカバー部材6とを備え、未使用状態では、カバー部材6は、第1の位置にあり、プランジャ11は、規制手段30により前記押圧操作が規制されており、未使用状態からカバー部材6を第2の位置に移動させた際、カバー部材6が規制手段30による前記押圧操作の規制を解除して、その押圧操作が可能となる。
