4-tert-Butoxybenzaldehyde is primarily used as an intermediate in organic synthesis, particularly in the production of fine chemicals and pharmaceuticals. Its unique structure makes it valuable for creating compounds with specific aromatic and aldehyde functionalities.

In the pharmaceutical industry, it serves as a building block for synthesizing active pharmaceutical ingredients (APIs) and other complex molecules. Its tert-butoxy group can enhance the stability and solubility of the resulting compounds, making it useful in drug development.

Additionally, it finds applications in the synthesis of fragrances and flavors due to its aromatic properties. The aldehyde group can undergo various reactions, such as condensation or oxidation, to produce compounds with desirable sensory characteristics.

In material science, it is utilized in the development of specialty polymers and coatings, where its chemical reactivity and aromatic nature contribute to the desired properties of the final product.