The aim of the research is to compare and select software tools for rapid prototyping of face retrieval systems with arbitrary structure (parallel, cascade, combined) that satisfy the requirements of the problem being solved. The relevance of development of modeling tools for face retrieval systems (FaRetSys) was shown, selection of software tools (Simulink + Matlab) was substantiated: methods are previously debugged in Matlab, and then integrated into Simulink blocks. The concept of organizing a library for modeling FaRetSys is proposed. Functions and the methodology of using the library in solving modeling problems are given from point of view the block composition concept. The developed library was used to solve the variational problem of selecting the structure and adjusting the parameters of FaRetSys based on mathematical modeling in Simulink. A synthesized system with a parallel structure confirmed the increased accuracy of FaRetSys by using parallel FaRetSys and making a decision based on a comparison of subsystems operation results.