The enrichment of palladium ions in organisms can harm organisms to a great extent. It is necessary and critical to develop molecular tools that can ratiometrically image Pd²⁺ in living cells. Herein, we have developed a new FRET-based ratiometric fluorescent probe (CR-Pd) for the specific determination of Pd²⁺ in living cells. Moreover, fluorescence imaging shows that CR-Pd could be used as a probe for the ratiometric visualization of Pd²⁺ in mitochondria.