Currently, big data has become the main driving force of the information society. It could change healthcare. The article by big data in healthcare are also analyzed. Personal medical data security issues are reviewed, recommendations are made for the development of the healthcare sector. The concept of Big Data refers not only to the size of data, but also to the process of creating value from it. Big Data can really improve the healthcare system, choose the appropriate treatment method and reduce other healthcare problems. Big Data now covers all areas of human life, including biological and medical. Big Data is not only a reality for biomedical professionals, but also an effective tool for understanding and searching for new knowledge. Clustering, cluster analysis is defined as an unsupervised learning approach for analyzing data into groups, usually grouping similar objects into classes called clusters. Cluster-based techniques attempt to learn and estimate these parameters from the supplied data. A global dataset of patients with different diseases and experiences will help. By processing this data, we can create databases with different samples so that the patient’s treatment plan is as appropriate and accurate as possible. This approach is already used in other areas of medicine, for example, for the recognition of X-ray images. Using fuzzy logic, machine learning and artificial intelligence algorithms, data from databases can be used to generate predefined patient treatment patterns. This can help determine the diagnosis and prescribe the right treatment in cases where doctors take a long time to decide on the right approach.