Abstract: Long noncoding RNAs, which lack protein-coding capacity, regulate various biological processes through diverse molecular mechanisms. lincRNA-p21 is a tumor suppressor gene and related to p53. lincRNA-p21 regulates p53 through MDM2, ING1b, p21 and other targets, to participate in the regulation of cell cycle, proliferation and apoptosis. lincRNA-p21 coordinates the Warburg effect through HIF-1α and participates in various biological functions. lincRNA-p21 is closely related to the prognosis and treatment of tumors. Therefore, lincRNA-p21 can be used as a biomarker for cancer diagnosis and prognosis. This paper reviews the recent progress in biological function of lincRNA-p21 and its mechanism in diseases.