Silymarin is a purified extract from the seeds of Silybum marinum L. (Asteraceae) also called “milk thistle”. Silymarin is widely used as a hepatoprotectant in the treatment of various liver disorders including hepatitis, cirrhosis and fatty acid infiltration due to alcohol and toxic chemicals. Mechanism of action of silymarin is still poorly understood. However, hepatoprotection can be attributed to its antioxidant effects which are mediated by scavenging of free radicals, decreasing formation of reactive oxygen species and inhibition of fatty acid peroxidation. Anti-inflammatory, antiapoptotic, anticarcinogenic, antiviral, anti-fibrotic and anti-angiogenic properties of silymarin have also been documented. This review presents a brief overview of the pharmacological features and therapeutic aspects of silymarin.