Abstract: Small nucleolar RNAs (snoRNAs) are non-coding RNAs in the nucleolus and are mainly responsible for the 2'-O-methylation and pseudouridine modification of rRNA. snoRNAs regulate various biological processes, such as tRNA modification, spliceosome snRNA modification, maintenance of the telomere structure, and alternative splicing of mRNA. Aberrant expression of snoRNA is related to cancer progression, and it may become a new target for cancer treatment. snoRNAs are stable and easy to detect in body fluids, so they can be used as a biomarker for clinical diagnosis and prognostic. This article reviews the biogenesis, classification, structure, and function of snoRNAs and introduces their potential role in the occurrence and development of hepatocellular carcinoma.