The objective of the study is to create an information system for fraud prevention that applies graph data structures in the work of credit and financial institutions. IDEF0 is used as methodological tools to describe the functions and interactions of the system and DFD diagrams to display data flows. The study includes an algorithm for detecting fraud, which is based on the graph structure and the nearest neighbor method. The main components of the system are the core of the graph platform in the Wolfram language and a web application in Java that converts JSON into graph data and visualizes them via the HTTP protocol. The developed functional model of the system displays all the main mechanisms and components, including interaction with external systems. The testing confirmed the correctness of the interface, algorithms and graph structure of the database. The testing covered three layers: interface, API and database, using Postman to check functionality and data integrity. The developed system for anti-fraud solutions demonstrated its effectiveness in automatic data search and comparison. The web application using Java b Spring Cloud and the graph platform in the Wolfram language provide high performance and accuracy in fraud detection. Functional testing confirmed the system’s compliance with the established requirements, making it a reliable tool for credit and financial institutions in the fight against financial crimes.