Objective: To quantitatively evaluate carotid atherosclerotic plaque by shear wave elastrography (SWE). Methods: SWE was performed in 183 patients with carotid atherosclerotic plaques, the corresponding mean, minimum and maximum elasticity value at different places (anterior wall, posterior wall and lateral wall) of plaques with different two-dimensional gray scale image features (hyperechoic and hypoechoic ) were obtained and statistically analyzed. Results: There were totally 133 hyperechoic plaques and 128 hypoechoic plaques. The mean, minimum and maximum elasticity value of hyperechoic plaque was (52.67±14.09)kPa, (40.94±15.94)kPa and (62.39±20.38)kPa, while of hypoechoic plaque was (16.83±6.47)kPa, (10.14±5.82)kPa and (24.76±8.56)kPa, respectively (all P<0.01). No statistical difference of elasticity value was found among different places of plaques with same gray scale image feature (all P>0.05, nor between two observers. Conclusion: The elasticity value measured with SWE can reflect the stiffness of plaques, therefore providing more information for quantitative assessment of carotid atherosclerotic plaques. Copyright © 2013 by the Press of Chinese Journal of Medical Imaging Technology.