To make weft yarn unevenness (Barre) which generates accompanying the switching of weaving conditions less conspicuous, in a loom in which elements related to the weft restranining force while performing a weaving operation of the loom.

A speed command signal to warp yarn-traveling members 3, 13 is corrected to the direction to eliminate generation of the weft yarn density unevenness accompanying switching at least two of textile texture, kind of weft, and weft picking density as elements related to the weft yarn restraining force in the loom 1 in which warp yarn 2 is set to travel by driving the warp yarn-traveling members 3, 13 by a speed command signal.