The present invention discloses weight-per-meter measuring device and method for fabric setting, and relates to detection technology. The weight-per-meter measuring device includes one electronic weighing instrument, one electronic length instrument, one operating and regulating unit, a display, a printer and a computer with corresponding software. Under the control of the computer, the weight-per-meter measuring device measures the length and the weight of the set fabric, calculates the square weight, compares with the standard amount and regulates. The present invention has easy manufacture, high precision, fast regulation, automatic control, high efficiency and other advantages.