To prevent the breakage of peripheral parts and the deterioration of the quality of woven fabric caused by the winding of trimmed selvage strip on a surface roller in a trimmed selvage treatment system to draw and discharge a trimmed selvage strip through the circumference of a surface roller or thereabout.

A sensor 9 sensing the movement of a trimmed selvage strip in a direction opposite to the drawing direction is placed at the downstream side of a surface roller. Since the abnormality in the treatment of trimmed selvage is automatically detected by the sensor 9, the operation of a loom can instantaneously be stopped by outputting an abnormality signal upon detecting the abnormality.