Flavonoids generate significant interest as these phytoconstituents exhibit anti-inflammatory, antimicrobial, antimutagenic, and anticarcinogenic properties. More than 5000 flavonoids have been identified; among these compounds are flavones, which are naturally available in the plant kingdom, including the main flavones tangeretin, apigenin, chrysin, nobiletin, luteolin, and baicalein. Structurally, flavones have a molecular formula of C15H10O2; the chemical structure of flavones is closely related to the development of their biological functions. In the case of their anticancer properties, both in chemoprevention and treatment, the hydroxyl group has been identified as the key element associated with the cytotoxic capacity of these biomolecules against cancer cells. Some of the anticancer mechanisms of flavones include the induction of apoptosis, cell cycle arrest in the G1 or G2/M phase, inhibition of enzymes involved in metabolism such as cytochrome P450, inhibition of reactive oxygen species (ROS) formation through the activation of phase II metabolizing enzymes, and inhibition of angiogenesis mediated by vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF). In the present chapter, the relationship between the structure and the potential anticancer mechanisms of flavones is detailed, supported by in vivo, in vitro, and in silico studies.