The radiation-resistant response of BaTiO₃ in the tetragonal and rhombohedral phases on exposure to 100 MeV Ag⁷⁺ ion irradiation was investigated by in situ X-ray diffraction (XRD) at room temperature (300 K) and low temperature (25 K), respectively. This study revealed that the BaTiO3 in rhombohedral phase retained crystallinity up to an ion fluence of 1x10¹⁴ ions/cm², whereas tetragonal phase amorphized at much lower fluence viz. 1x10¹³ ions/cm². The in situ XRD along with Raman spectroscopy studies revealed that BaTiO3 in rhombohedral phase is more radiation resistant than that of tetragonal phase. The density functional theory (DFT) calculations confirmed higher bond strength of rhombohedral phase as compared to tetragonal phase, which supported the experimental result of higher radiation stability of rhombohedral phase. The theoretical predictions on high-temperature phase will be of relevance to the nuclear waste applications.