A tube clamp apparatus and a tube connecting apparatus having high durability and improved operability when an operator locks these apparatuses are provided. A tube connecting apparatus comprises a first clamp and a second clamp, each pressing to hold two flexible tubes 8, 9. The tubes are placed at a lower jaw portion of the second clamp and pressed to a flat state by pressing force applied thereto a direction of an arrow F. A hook section 310 having hook portions divided into plural pieces is set up at an upper jaw portion of the second clamp, and the hook portion B 312 is made of a POM elastic member having, on one side thereof, a protruded portion 314 protruded from other adjacent hook portions. When pressing force is applied to the upper jaw portion, the hook portion B 312 protruded from the other adjacent hook portions is elastically deformed and engaged with a POM-made roller B 317 to prevent back-tracking of the hook section 310.