N-Methylthiourea is primarily used in organic synthesis as a reagent for the preparation of various heterocyclic compounds. It serves as a key intermediate in the production of pharmaceuticals, particularly in the synthesis of antithyroid agents and other therapeutic drugs. Additionally, it is employed in agricultural chemistry for the development of pesticides and herbicides, where it acts as a precursor or active ingredient. In research, N-Methylthiourea is utilized to study enzyme inhibition mechanisms, particularly those involving urease and other enzymes. Its role in polymer chemistry includes acting as a cross-linking agent or modifier in the production of specialty polymers.