Provided is a liquid feeding device, including: a test container including a first accommodation portion, a second accommodation portion, and a third accommodation portion each accommodating a liquid, a first flow path connecting the first accommodation portion and the second accommodation portion to each other at respective upper end positions thereof, and a second flow path connecting the second accommodation portion and the third accommodation portion to each other at respective upper end positions thereof, in which at least a portion forming an upper wall surface of the second accommodation portion has flexibility; and a pressing machine which includes a first pressing portion and presses the portion forming the upper wall surface of the second accommodation portion at a position closer to the first flow path from a center in a liquid feeding direction towards an inside of the second accommodation portion from an outside by the pressing portion, in which the liquid accommodated in the second accommodation portion is fed to the third accommodation portion by pressing the portion forming the upper wall surface of the second accommodation portion with the pressing machine.