<p>Solar cells deployed in extra-terrestrial environments encounter high energy particles and ionizing radiation that compromise their stability, intensifying lattice defects. The computational examination of the radiation resistance of perovskite solar cells for their prospective utilization in extra-terrestrial environments is conducted. We simulated the (1) blackening of the glass substrate and (2) displacement defect caused by proton radiation in perovskite solar cells. The reduced transmittance of glass substrate causes short-circuit current (<i>J</i>_SC). To simulate the irradiation-caused defect degradation, we utilized the defect model, which replicated the experimental observation of large <i>J</i>_SC and small decays in open-circuit voltage (<i>V</i>_OC) with fluence of 1&#xa0;MeV proton radiation. Simulation shows robust radiation resistance of perovskite as performance remains stable for 1&#xa0;MeV proton fluence up to 10¹³ particles.cm⁻². The results derived from the simulation reinforce the applicability of perovskite in space environments.</p>