The paper proposes an approach for visualization of access control systems based on triangular matrices. The approach is used for visualization of access control security model that based in methods of RBAC and Take-Grant. In comparison with regular access matrices, the sparseness of triangular matrices is less, and the approach is able to visualize nesting at the level of rights. The paper outlines a new triangular visualization model, its interpretation, management methods, and the results of experiments for visualization of an access control system in an IT company.