【Abstract】Objective: To compare and analyze the value of Young''s modulus of the unilateral hydronephrosis and the contralateral normal renal parenchyma in children, so as to explore the value of shear wave quantitative elastography in the hydronephrosis of children. Methods: The values of Young''s modulus of bilateral renal parenchyma in 60 children with unilateral pyelonephrosis were measured by shear wave elastic imaging in May 2015 ?May 2018 years in our hospital. The normal side kidney was taken as the control group, and the data were compared and analyzed. Results: The parenchyma Young''s modulus of the hydronephrosis was significantly higher than the young''s modulus of the contralateral normal renal parenchyma. There was a significant difference between the two. The deeper the degree of renal fibrosis, the higher the young''s modulus, the more serious the damage of the renal parenchyma. Conclusion: The shear wave quantitative elastography provides the diagnostic information outside the conventional two-dimensional ultrasound examination, and provides an important reference for the clinical formulation of the treatment scheme.