Bismarck Brown Y is primarily used as a biological stain in histology and microbiology. It is effective in staining tissues for microscopic examination, particularly in highlighting certain cellular structures. In textile industries, it serves as a dye for coloring fabrics, leather, and paper, providing a range of brown shades. Additionally, it is utilized in the manufacturing of inks and coatings, where its coloring properties are advantageous. The dye is also employed in some educational and research settings for demonstrating staining techniques and studying cell morphology.