This paper presents a compensation method for an accelerometer to measure acceleration data accurately when a robot manipulator moves slowly. Although the accelerometer works fine under the fast movement of a robot manipulator, low cost accelerometers provide relatively inaccurate acceleration data under slow movements. In order to correct the error of the sensor data in the slow motion, correction factors are obtained experimentally. Then those corrected data are used for the disturbance observer. Experimental studies of the position control of a robot manipulator are conducted by applying the DOB (Disturbance Observer) control using corrected acceleration data.