Diosmin is of potential interest for its possible role in human health. Diosmin is a flavone glycoside that is a member of the class of flavonoids, which are secondary metabolites found in large quantities in plants and vegetables. Diosmin is specifically the glycoside of the aglycon diosmetin (3′, 5, 7-trihydroxy-4′-methoxyflavone), which is found naturally and in large quantities in citrus fruits as well as in a number of herbal medicines. It is useful in the treatment of a number of illnesses. Its biological roles, including its use as a phlebotonic drug and its extraordinary antioxidative, antihyperglycemic, anti-inflammatory, anticancer, and antibacterial activity, have been highlighted by numerous in vitro and in vivo research. We looked at a summary of diosmin’s chemistry, biochemistry, and pharmacology, focusing on its main biological characteristics, therapeutic uses, and possible targets of action after activation or blockage of the pathways linked to its use.