o-Tolylthiourea is primarily used as a corrosion inhibitor in industrial applications, particularly in cooling water systems and metal processing. It effectively protects metal surfaces by forming a protective layer that prevents oxidative damage and extends the lifespan of equipment. Additionally, it finds use in the synthesis of certain pharmaceuticals and agrochemicals, where it acts as an intermediate in the production of active compounds. In research, it is employed as a reagent in organic synthesis for constructing complex molecules. Its role in inhibiting enzyme activity also makes it valuable in biochemical studies.