Accurate evaluation of the degree of liver fibrosis in patients with chronic liver diseases (CLD) is crucial, as liver fibrosis is important in determining the prognosis of liver diseases. Currently, liver biopsy (LB) is considered the gold standard for staging liver fibrosis or cirrhosis. However, utilization of LB in clinical practice is often limited because of its invasive nature, sampling error and interobserver variability. Recently, transient elastography (TE) was introduced as a noninvasive, highly reproducible technique for assessing the degree of liver fibrosis. After extensive studies, TE is now regarded as a reliable surrogate marker for grading the severity of liver fibrosis in patients with CLD. In the past few years, the role of TE in monitoring liver stiffness and determining prognosis in patients with chronic hepatitis B (CHB) or chronic hepatitis C (CHC) who are undergoing antiviral treatment has been investigated. In patients with CHB, liver stiffness values decrease with antiviral treatment. TE can also be used to predict the incidence of liver-related events during antiviral treatment. In patients with CHC, TE can be used to monitor potential regression of liver fibrosis after antiviral treatment and may predict the treatment outcome of CHC. In addition, TE is an adjunct tool for distinguishing inactive hepatitis B virus carriers from patients with chronic active hepatitis. This review article discusses the important findings from recent studies focusing on the clinical application of TE in patients with chronic viral hepatitis who are undergoing antiviral treatments.