PURPOSE: To provide a cloth winding roll exchanging device for a weaving machine which has a means to rapidly detect defecting winding.

CONSTITUTION: A cloth winding roll exchanging device for a weaving machine is formed so that when a cloth winding roll 8 located at the winding drive part 3 of a weaving machine 1 having a pair of rolls 5 and 6 is brought into a fully wound state, the cloth winding roll 8 is delivered more frontward than the drive part 3 and thereafter, an empty roll 16 is fed to the winding drive part 3, woven cloth 4 is cut between the winding drive part 3 and the delivered cloth winding roll 8, and a cut part on the winding drive part 3 side is wound around the empty roll 16. A tension detecting means 100 to detect the tension of the woven cloth 4 is provided. A detected value detected at a point of time when a given time starting from change of the cloth winding roll lapses is compared with a preset value by means of a control means 120 to decide whether winding is defective or indefective.