Long noncoding RNAs (lncRNAs) are involved in the regulation of normal physiological processes in humans, while also participating in the development and progression of different cancers. Investigations have indicated that the deregulation of lncRNAs is involved in diverse malignant cellular processes, such as proliferation, anti?apoptosis, migration, invasion, and epithelial?to?mesenchymal transition. A major lncRNA candidate for involvement in cancer is MIAT, the aberrant expression of which has been observed in multiple cancers and functions as an oncogenic factor, including in lung cancer, breast cancer, gastric cancer, liver cancer, and prostate cancer. MIAT thus has immense potential value in clinical applications, holding promise as a biomarker and therapeutic target. This work summarizes current knowledge of the biological functions and underlying mechanisms of MIAT in the development and progression of cancers.