ObjectiveTo predict whether antiviral therapy is required in patients with chronic hepatitis B virus （HBV） infection and an age of ≤30 years by establishing a noninvasive model， and to investigate the diagnostic value of this model. MethodsA retrospective analysis was performed for the clinical data of 175 patients with chronic HBV infection who were admitted to Shenzhen Third People’s Hospital from January 2017 to January 2023 and met the inclusion criteria， and according to the results of liver biopsy， they were divided into treatment group with 41 patients （with indications for antiviral therapy） and observation group with 134 patients （without indications for antiviral therapy）. The two groups were analyzed in terms of the indicators including clinical data， imaging examinations， and serum biochemical parameters. The univariate and multivariate Logistic regression analyses were used to investigate the parameters affecting the indication for antiviral therapy， and different models for predicting the need for antiviral therapy were constructed based on related parameters. The receiver operating characteristic （ROC） curve was used to compare the diagnostic value of different models. The independent-samples t test was used for comparison of normally distributed continuous variables between groups， and the Mann-Whitney U rank sum test was used for comparison of non-normally distributed continuous variables between groups； the chi-square test or the Fisher’s exact test was used for comparison of categorical data between groups. ResultsThere were significant differences between the treatment group and the observation group in alanine aminotransferase， ferritin， total cholesterol （CHOL）， triglyceride， platelet count， liver stiffness measured by sound touch elastography （STE）， and procollagen III N-terminal propeptide （PIIIP） （all P<0.05）. The multivariate Logistic regression analysis showed that CHOL （odds ratio ［OR］=0.4， 95% confidence interval ［CI］： 0.2‍ ‍—‍ ‍1.0）， STE （OR=1.5， 95%CI： 1.0‍ ‍—‍ ‍2.1）， and PIIIP （OR=1.1， 95%CI： 1.0‍ ‍—‍ ‍1.1） were independent predictive factors for the indications for antiviral therapy. Model 1 （STE+PIIIP+CHOL）， model 2 （STE+PIIIP）， model 3 （STE+CHOL）， model 4 （PIIIP+CHOL） had an area under the ROC curve of 0.908， 0.848， 0.725， and 0.725， respectively， while STE， PIIIP， and CHOL used alone had an AUC of 0.836， 0.725， and 0.634， respectively， suggesting that model 1 had the largest AUC， with a specificity of 77.34% and a sensitivity of 96.36%， and had a significant difference compared with STE， PIIIP， CHOL， and the models 2， 3， and 4 （Z=0.21， 3.08， 3.06， 3.23， 0.89， and 0.88， all P<0.05）. ConclusionThe noninvasive model established based on CHOL， STE， and PIIIP has a good value in predicting the need for antiviral therapy in patients with chronic HBV infection and an age of ≤30 years.