Apex Angle, azimuth angle, and the mud pressure in bottom are critical parameters while drilling. But the current gradiograph can not meet the operating requirements of deep hole drilling not only in operating environment but also in precision. So, a gradiograph was designed which based on fiber optic gyroscope and accelerometer, the gradiograph is used in rope core drilling. When completed, a numbers of tests were operated, and the experimental result proved that the instrument satisfy the demands of practical engineering.