Methylhydrazine dihydrochloride is primarily used in organic synthesis as a versatile reagent. It plays a key role in the preparation of various heterocyclic compounds, which are essential in pharmaceutical research and development. The compound is also utilized in the synthesis of hydrazine derivatives, which are important intermediates in the production of agrochemicals and dyes. Additionally, it finds application in the field of polymer chemistry, where it is employed in the modification of polymers to enhance their properties. In analytical chemistry, it serves as a derivatization agent for the detection and quantification of specific analytes. Its reactivity and stability make it a valuable tool in numerous chemical processes.