As a result of the development of computer science and informatics, the amount of data has become greatly digested and does not end up storing this data, as it represents the memory of the institution and real wealth that can be neglected and forgotten or invested in a smart and academic way to draw up policies and future plans for the institution on a vision and insight that describes the failures and success of the institution and predicts the imposition of future improvement. It provides its users with the ability to explore knowledge from a huge amount of data and focuses on sensing and future predictions, exploring patterns, behavior and trends, allowing to estimate the right and sound decisions and take them at the right time, develop appropriate solutions to problems, plan, develop and update all areas of the organization.In light of the huge amount of data in computer systems and networks in educational institutions, including university libraries, it was necessary to find a technique to collect, analyze and classify data of large sizes in order to reach knowledge that leads to making the right decisions and predicting unknown future values, so the study aimed to introduce the concept of the process of data mining and revealing its implications and showing its role in discovering knowledge and studying the types of relationships that arise between data, collecting and classifying it.To mine university library data. The study concluded that data mining technology has the optimal tools for analyzing and processing big data in university libraries that help a lot in predicting future values, and in light of this, the right decisions are made in improving services in this type of libraries.