The tensile properties of ultra-high performance concrete (UHPC) with ceramic fiber volume fractions of 0%, 0.3%, 0.6%, 0.9%, and 1.2% were evaluated through splitting tensile tests at high temperatures (200–800 ℃). The effects of temperature and fiber content on the tensile strength of UHPC at elevated temperatures were investigated. Based on the tensile strength data after high-temperature exposure, the microstructure and phase composition of UHPC subjected to different temperature conditions were analyzed using scanning electron microscopy (SEM). The results indicate that the heating temperature is the primary factor influencing the tensile strength of UHPC, with the tensile strength being highly sensitive to temperature variations. As the temperature increases, the splitting tensile strength of UHPC exhibits a linear decline. The tensile properties of ceramic fiber reinforced UHPC at high temperatures are superior to those of unreinforced UHPC. Notably, when the ceramic fiber content is 0.9%, the loss in splitting tensile strength of the ceramic fiber reinforced UHPC after high-temperature exposure is the least.