The present invention provides an infusion pump capable of preventing a bubble sensor from erroneously detecting existence of a bubble by avoiding a part of the medicinal solution remaining inside a portion where a flow path of an infusion tube is narrowed by a bubble sensor. In an infusion pump 1, a bubble detection unit 51 includes: a pushing member 320 as a first member disposed at an access cover 5 and having an ultrasonic transmitting unit 321 and a receiving member 330 as a second member disposed at a main body 2 and having an ultrasonic receiving unit 31 configured to receive ultrasonic from the ultrasonic transmitting unit 321. A second space BH2 to narrow a flow path of an infusion tube 200 on a more downstream side than a bubble detection unit 51 in a feeding direction to feed medicinal solution 171 of the infusion tube 200 is set smaller than a first space BH1 to narrow the flow path of the infusion tube 200 between the first member and the second member in a state that the access cover 5 is closed.
