Propyl methanesulfonate is primarily used as an alkylating agent in organic synthesis, where it introduces propyl groups into various molecules. It is commonly employed in the preparation of pharmaceuticals and agrochemicals, particularly in the development of compounds with specific biological activities. Additionally, it serves as a reagent in the modification of polymers and other materials to enhance their properties. Due to its reactivity, it is also utilized in research laboratories for studying alkylation mechanisms and DNA interactions.