Abstract:RQD grading is widely used to evaluate the integrity of rock mass. The traditional RQD grading method uses manual measurement for operation, with high labor intensity and low work efficiency. To solve this problem, this paper takes Julong Copper Mine as the engineering background and proposes a RQD grading method based on Image J analysis function. As for the method, firstly shoot the drilling core image to obtain the drilling core information, number the drilling cores of different lengths with Image J, get the core lengths of different numbers by the measurement and analysis function, and at last calculate the RQD value. The drilling core cataloging is completed quickly. The error between the calculation results and the results obtained by the traditional RQD grading method is only 0.5% to 1.0%, with good consistency and high accuracy. The method is convenient and efficient, and is suitable for practical engineering applications, especially in plateau areas and areas with heavy conditions.