ABSTRACT The topic of this final paper is data Protection in Office Operations. It is very important to protect data, be it physical or electronic protection, so that a certain organization can run its business smoothly. The paper approaches the definition of office operations, which can be defined as the handling of files, then their classification, recording, and search. We distinguish six principles of office business: simplicity, transparency, expediency, uni-formity, economy, and legality. Data security and protection of information systems can be considered as an obligation of IT experts, because today's world is characterized by information insecurity, so it is very important that computers and data are adequately protected. It is important to protect data with physical or electronic protection. When we talk about phys-ical security, then we mean the protection of information or infrastructure due to natural phe-nomena, such as fires, floods and a like, but also care about ensuring adequate conditions and choosing the position of the premises. In addition to physical data protection in office operations, there is also electronic protection, which protects data from destruction, unauthorized intrusions and the like. The types of elec-tronic protection, such as passwords, encryption, and digital watermark, are listed and defined below. Croatian Post is the best example of how to do business because in recent years it has undergone a comprehensive digital transformation. Their focus on electronic services and digital business puts cyber security first, as they know this is very important if they want to be sure that they will be able to run their business on a daily basis without interruption and without fear of hacker attacks.