Apoptosis is a genetically controlled response by which eukaryotic cells undergo programmed cell death. Tissue homeostasis requires a balance between cell proliferation and death. Apoptosis and proliferation are linked by cell cycle regulators, and apoptotic stimuli affect both cell proliferation and death. The present study has been designed to evaluate the effects of age on hepatocyte apoptosis and proliferation in male rats under normal physiological conditions in vivo. The study was performed on 24 white male rats, distributed in four age groups ( newborns, youngs, adults, senescents). Apoptosis was detected in liver sections by the in situ oligo ligation (ISOL) assay, using an ApopTag ISOL assay kit. To evaluate the proliferative activity of hepatocytes the method of flow cytometry was used. It was shown that aging influences the susceptibility of hepatocytes to apoptosis and poliploidy. The most high rate of apoptosis is characteristic for young and senescent age groups and correlates with increased rate of ploidy of hepatocytes. It can be consider that apoptosis in the liver could have the protective effect during aging.