An echogenicity quantification method and a calibration method for ultrasonic device using echogenicity index are disclosed. The method includes: receiving an ultrasound image which comprises a plurality of grayscale pixels; choosing a region of interest (ROI); calculating the values of the grayscale pixels in ROI to obtain average value and standard deviation; excluding pixels in ROI with the grayscale value smaller than the sum of the minimum value in the grayscale image and the product of a first scaling factor and the standard deviation, and larger than the sum of the average value and the product of a second scaling factor and the standard deviation; averaging the values of the remaining grayscale pixels in ROI to obtain an average value of interest; choosing a reference region; averaging the values of the remaining grayscale pixels in the reference region to obtain an average value of reference; and calculating the difference between the average value of interest and the average value of reference to obtain an echogenicity index.