Objective To investigate the elastic changes in the liver of early cholangitis after biliary atresia (BA) operation. Methods 59 children who were diagnosed with biliary atresia in ultrasound and confirmed by operation from February 2019 to February 2020 were analyzed. In addition, whether cholangitis occurred in infants during the first month of operation was divided into cholangitis group and non-cholangitis group to investigate the changes of liver elastic modulus in the two groups before and after surgery in January. Results There was a statistically significant difference between the preoperative and postoperative liver elastic modulus values in the non-cholangitis group and the cholangitis group respectively（P<0.05）. The liver elastic modulus of cholangitis group was significantly higher than that of the non-cholangitis group in January after surgery（P=0.001）. The preoperative liver elastic modulus values of all infants showed a linear relationship with the age of the day(R=0.258，P=0.000), and the greater the age, the greater the elastic modulus. However, there was no significant linear correlation between the daily age and the liver elastic modulus in January（P=0.055）. Conclusion Ultrasonic real time shear elastic imaging(SWE) technique has certain value in the detection of liver stiffness in infants with biliary atresia and the changes of liver stiffness after surgery in early cholangitis.