Fetuin-A, also known as alpha-2-Heremans-Schmid-glycoprotein (Ahsg), is a multifunctional molecule with diverse roles in biological processes such as mineralization, tumor growth, and inflammation. This review explores the involvement of Ahsg in various cancers, including liver, breast, prostate, colorectal, brain, osteosarcoma, and lung cancers. In many cancer types, Ahsg promotes tumor growth, invasion, and metastasis through various mechanisms, including cellular adhesion, spreading, chemotaxis, and modulation of cell-growth signaling pathways. Additionally, Ahsg has been implicated in the regulation of inflammatory cytokine production, making it a potential marker of inflammation in cancer. The complex interplay between Ahsg and cancer progression highlights its potential as a diagnostic biomarker and therapeutic target in various cancers. However, further research is needed to fully elucidate the mechanisms of action of Ahsg in cancer and to explore its clinical implications in cancer diagnosis, prognosis, and treatment.