(2-Phenylethyl)phosphonic acid is primarily utilized in the field of organic synthesis and materials science. It serves as a key intermediate in the preparation of various phosphonate esters, which are important in the development of flame retardants and plasticizers. The compound is also employed in the synthesis of biologically active molecules, particularly in the pharmaceutical industry, where it contributes to the creation of drugs with potential therapeutic effects. Additionally, its phosphonic acid group makes it valuable in chelation processes, where it can bind to metal ions, aiding in the purification of metals or in the formulation of metal-based catalysts. In agriculture, derivatives of this chemical are explored for their potential use as herbicides or plant growth regulators, leveraging its ability to interact with plant biochemical pathways.