To study the effect of natural product Oblongifolin C(OC)，a polycyclic polyprenylated acylphloroglucinol isolated from Garcinia yunnanenis Hu，on mitochondrial function and apoptosis.Methods:Wild type and bax/bak-/-mouse embryonic fibroblast MEF and human colon carcinoma cell line HCT116 were used as in intro model systems.Flow cytometry，confocal microscopy and immunoblotting were performed to detect the impacts of OC on ROS，mitochondrial function and apoptosis.Results:OC results in mitochondrial degradation and ATP depletion by increasing ROS production，disrupting mitochondrial outer membrane，reducing mitochondrial membrane potential，and finally induces apoptotic cell death.Conclusion:OC induces apoptosis through multiple pathways and it might be an attractive anticancer compound for the treatment of tumors.