Through several studies exploiting next-generation sequencing, we are obtaining a clearer picture of the complex genetic and molecular landscape of hepatocellular carcinoma (HCC). Consistent with the findings of other cancer types, telomerase reverse transcriptase (TERT) promoter mutations have been frequently reported in HCC. C228T and C250T are two major types of hot spot mutations in the TERT promoter region. Besides, in hepatitis B virus (HBV)-related HCC cases, the TERT promoter is recurrently interrupted by integration of HBV DNA. TERT promoter mutations are thought to be an early event in HCC carcinogenesis, and they are significantly associated with disease progression. In this review, we provide an updated overview of the somatic mutations in the TERT promoter region and discuss their possible roles in the development of HCC.