YCa4O(BO3)3 (YCOB) and GdCa4O(BO3)3 (GdCOB) crystals are promising piezoelectric materials for high-temperature sensing applications. The high-temperature condition is accompanied by hard irradiation, such as in a nuclear power plant. In this study, the electroelastic properties of YCOB and GdCOB crystals irradiated by different doses of 6 MeV Xe23+ (1013, 1015, and 1016 ions/cm2) were studied in the temperature range of 25-850 ��C. YCOB and GdCOB crystals exhibit good electrical resistivity stability with irradiation, where the resistivity of >108 ����cm is achieved @700 ��C. Meanwhile, the electroelastic properties are found to maintain similar values, with variations being less than 8% after irradiation. The band gaps of the YCOB and GdCOB crystals are narrowed upon irradiation, leading to a slight decrease in electrical resistivity, while the slight increase in the dielectric permittivity after irradiation is associated with the irradiation-induced distortion of the structure and weakening of chemical bonding. All the irradiation resistant properties demonstrate that the bulk YCOB and GdCOB crystals are good candidates for use in high-temperature piezoelectric sensing under harsh environments including hard irradiation.