The 5-HT3 receptor is a ligand-gated ion channel activated by the neurotransmitter serotonin. Receptors of this subtype have been localized to several regions of the brain, and appear to be involved in many neuronal functions including responses to alcohol and other drugs of abuse. There is an extensive and growing literature indicating that 5-HT3 receptors are involved in several facets of alcohol seeking behavior, alcohol intoxication and addiction. In addition, there is strong evidence that alcohols, including ethanol, alter the function of the 5-HT3 receptor, possibly through actions on the receptor protein itself. In this article, our current understanding of the role of the 5-HT3 receptor in alcohol abuse and alcoholism will be reviewed. In addition, an overview of current understanding of the mechanism of alcohol actions of the receptor is provided.