This article analyzes the influence of an anti-diffractor on the upper edge of a noise barrier's acoustic efficiency based on the results of mathematical modeling in the COMSOL Multiphysics software. Initially, a comparison was made between the modeling results of the acoustic efficiency of a thin barrier of infinite length and calculations using the Kurze formula. The effect of the installation angle of the anti-diffractor on the barrier's acoustic efficiency was analyzed. The values of the superstructure's acoustic efficiency at different diffraction angles were determined. For visualization purposes, changes in sound pressure level (SPL) within the acoustic domain at the mean geometric frequency of 1000 Hz are presented for different angles of anti-diffractor installation.