Abstract: The effect of frequency on the imaging was focused by this paper, an external vibrator which generated sine signals with different frequency were used to compress tissues, then a set of RF echo data were received by ultrasonic transducer. The continuous tissue strain field was obtained by motion estimation and strain estimation. The elastograph is obtained clinically as instantaneous strain imaging, thus the frequency of compression will affect the imaging results. The amplitude of strain decreased with the increasing of frequency, which will affect the image contrast. The results also showed that the mean of continuous strain could remain stable when frequency changed, which showed obviously different for different tissues. Compared with instantaneous strain, the mean of continuous strain has more profoundly clinical application significance.