N,N'-Diisopropyl-O-methylisourea is primarily used in organic synthesis as a reagent for the methylation of various compounds. It is particularly effective in introducing methyl groups to amines, alcohols, and thiols, facilitating the production of methylated derivatives. This chemical is also employed in the synthesis of pharmaceuticals, where precise methylation is crucial for the desired biological activity. Additionally, it serves as a valuable intermediate in the preparation of agrochemicals, contributing to the development of pesticides and herbicides. Its role in modifying chemical structures makes it a versatile tool in research and industrial applications, enhancing the efficiency of synthetic processes.