The fluid supply device includes a first connection portion and a second connection portion that connect the first container and the second container that store the fluid, a first flow path that is in communication with the first connection portion, A second flow path communicating with the first flow path, a joining section where the first flow path and the second flow path join together, a suction section that sucks the fluid from the joining section and delivers the fluid from the delivery section, Wherein a flow resistance of one of the first flow path and the second flow path is higher than that of the other flow path and the flow rate of each of the first flow path and the second flow path during operation of the suction section is A resistance section connected to the resistance section and switching between high and low of a difference in pipe resistance between the first flow path and the second flow path ,including.流体供給装置は、流体を貯留した第1容器および第2容器を接続する第1接続部および第2接続部と、前記第1接続部に連通している第1流路と、前記第2接続部に連通している第2流路と、前記第1流路と前記第2流路とが合流する合流部と、前記合流部から流体を吸引して送出部から送出する吸引部と、前記第1流路と前記第2流路に対して、一方が他方に対して管路抵抗が高く、かつ、前記吸引部の動作時における前記第1流路および前記第2流路それぞれの流量がゼロ超となるように管路抵抗の差を発生する抵抗部と、前記抵抗部に接続され、前記第1流路と前記第2流路とで管路抵抗の差の高低を切り替える切替部と、を含む。