To extend the service life of a tube, and to reduce adverse effect on a fluid to be delivered, in a tube pump.

This tube pump 1 includes: a housing 3 in which cylindrical inner wall surface 21 is formed; a tube 4 arranged in a ring shape; a pressing member 5 pressing the tube 4; an eccentric rotor 6 eccentrically moving the pressing member 5. A pressed part of the tube 4 is moved in one direction by eccentric movement of the pressing member 5 to perform pump action for delivering a fluid in the tube 4. An inner wall surface of the housing 3 is displaceably configured so that a tube maximum pressing amount may be varied, and opens the pressing of the tube 4 after the pump action is started. Since the pressing load imposed on the tube 4 is relieved after the start of the pump action, the damage of the tube 4 is prevented, and adverse effect such as breakage of a constituent molecule included in the fluid in the tube 4 is reduced.