PURPOSE: To detect the abnormality of an oscillating device for a casting mold and to prevent an accident such as breakout by detecting the actual stroke length and oscillation frequency of said oscillating device and comparing the same with the prescribed values which are preliminarily calculated.

CONSTITUTION: A detector 24 is installed in a part 12 for oscillating and driving a casting mold. The actual stroke length and oscillation frequency of the mold 2 are detected by said detector and are inputted to a control device 20. The device 20 compares at all times the same with the prescribed oscillation frequency and stroke length which are preliminarily calculated. When the difference therebetween exceeds a specified value, the control device judges the abnormality of the oscillating device for the casting mold and issues an emergency stop signal to pinch rolls 4 and respective motor control panels 10, 18 for oscillating the mold thereby preventing a serious accident such as breakout.