The emergence of the "Protein Corona" is a pivotal concept in bioinformatics and nanotechnology, crucial for understanding nanomedicine delivery and nanoparticle–biological entity interactions. After entering a biological fluid, such as blood, nanoparticles (NPs, such as nanomedical carriers) are quickly coated with proteins, forming a protein interface layer called the protein corona. An in-depth investigation into the protein corona is essential for elucidating the biological ramifications of NPs and their prospective applications within the medical field and beyond. To advance our understanding of the intricate interactions between NPs and biological systems, we have developed PROTCROWN, the inaugural protein corona database. This resource systematically curates and organizes data relevant to the protein corona, facilitating advanced analysis and research in the field. It provides a convenient data query platform for researchers and supports data visualization and analysis. Our database, PROTCROWN, is accessible at http://www.protcrown.cn.