Abstract: Cadmium (Cd2+) is a toxic heavy metal element that does severe harm to health. Since Cd2+ is known to induce apoptosis in a variety of cell types, this study investigated the apoptotic effects and mechanisms of Cd2+ on Siberian tiger fibroblast cells. This research observed morphological alterations with confocal microscopy and transmission electron microscopy, performed 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and detected apoptotic rates, cell cycle progression, mitochondrial transmembrane potential and intracellular calcium homeostasis. The results demonstrated that typical apoptotic morphological alterations occurred after cadmium treatment. Cadmium exerted a strong inhibitory to the proliferation of Siberian tiger fibroblast cells and induced apoptosis in a dosage and duration dependent manner. Cell cycle was arrested at G0/G1 phase, mitochondrial transmembrane potential dropped and calcium homeostasis was disturbed. It is concluded that cadmium induced apoptosis of Siberian tiger fibroblast cells via arresting cell cycle progression, reducing mitochondrial transmembrane potential and disturbing intracellular calcium homeostasis.