A needle does not come off even if a high back pressure occurs at the skin upper section. Thus, the drug leakage from the skin can be prevented. A drug administration device 1 includes a tubular section 2 having a fluid chamber 7 capable of accommodating a drug and a discharge section 22, a pusher member 3 moving within the tubular section 2, a grip section 4, and a connection section 5. The pusher member 3 includes a rod-shape plunger 31 and a gasket 32. The grip section 4 is disposed along the outer periphery of the tubular section 2 and kept away from the tubular section 2, and the connection section 5 is formed between the tubular section 2 and the grip section 4.