To provide a drug solution delivery device which is applied in delivering a drug solution such as insulin into a human body and can correctly deliver the drug solution.

Umbrella valves 138, 139 disposed on the midway of a flow path for sending a drug solution into a human body from a drug solution bag 110 for storing the drug solution by a sending portion 130 are held on both ends, and equipped in umbrella-like portions 138B, 139B with shock absorbing portions 138F, 139F for diverting a force from valve abutting surfaces 140D, 131H. By having the shock absorbing portions 138F, 139F, the valves are deformed and abut while diverting the force applied when the front end portions 138C, 139C abut on the valve abutting portions 140D, 131H. Thus, the influence of shape forming error can be reduced and a predetermined valve opening pressure can be achieved, so that the drug solution delivery accuracy can be improved.