Background <p>This study focuses on the Monte Carlo simulation of a prompt-gamma activation analysis (PGAA) system to assess its efficiency and reliability for elemental analysis. The main objective is to evaluate neutron and photon energy spectra and spatial distributions across critical components of the setup.</p> Method <p>The PGAA system was modeled using the PHITS Monte Carlo code. Energy spectra of neutrons and photons were investigated at key points, including the collimator shielding, neutron guide, beam shaper, irradiation chamber, Teflon sample, HPGe detector, and beam stop. Spatial distributions of fluxes were analyzed in the YZ plane and along longitudinal (z) and transverse (y) directions.</p> Result <p>The neutron flux was found to be highly collimated and efficiently moderated, exhibiting a thermal peak near the irradiation chamber, which enhances sensitivity for elemental analysis. Photon flux, while more diffused, remained effectively controlled due to adequate shielding. The system demonstrated high spatial and energy selectivity, minimized off-axis losses, and reduced background in sensitive regions.</p> Conclusion <p>The results confirm the effectiveness of the simulated PGAA system for precise analytical applications. The study highlights the importance of optimized component arrangement and robust shielding design to improve performance and reliability.</p>