Butyl isothiocyanate is primarily used in the field of agriculture as a natural pesticide and herbicide due to its ability to deter pests and inhibit the growth of unwanted plants. It is also employed in research laboratories for studying its antimicrobial and antifungal properties, which are valuable in developing new biocides. Additionally, it finds application in the food industry as a flavoring agent, imparting a pungent, mustard-like taste to certain products. Its role in organic synthesis is notable, where it serves as a building block for creating more complex chemical compounds.