A method of controlling the cutting feed speed of a saw frame of a band-sawing machine or a similar machine, whereby the change of cutting resistance to the saw blade is detected by sensing the change of load on the back of the saw blade or the change of pressure of an oil pressure cylinder supporting the saw frame and by transforming such change into a voltage change or amperage change by means of a piezo-electric element, the flow rate of a flow control valve provided at the pressure oil discharge circuit of the oil pressure cylinder being controlled by said detected voltage or the like and thereby the cutting feed speed being changed in response to the change of cutting resistance so as to maintain the cutting resistance to the saw frame at an optimum value.