PURPOSE: To provide a saw blade tension automatic regulating device for a sawing machine through which tension force accompanying the strain of a housing yoke can be regulated, and the position of a wheel is optimumly regulated to the saw blade even if the tension force of the saw blade is changed, and flange sounding and the breakage of the saw blade which are due to the strain of the housing yoke resulting from the variableness of the tension force can be automatically regulated, and operational performance is, therefore improved.

CONSTITUTION: A saw blade tension automatic regulating device for a sawing machine is provided with a position detecting sensor 41 to detect the position of a saw blade B, an arithmetic processor 43 for processing the position of the saw blade on a detection signal issued from the position detecting sensor 41, and a driving device 45 which adjusts the position of the saw blade to its optimum position by rotating an adjusting screw 47 in both directions on the command of the arithmetic processor 43.