Introduction: Nanoparticles of silver have many important applications and are among the most commonly used nanomaterials. They are increasingly used in a variety of both medical and consumer products which includes: spectrally selective coating for solar energy absorption and intercalation material for electrical batteries, as optical receptors, polarizing filters, catalysts in chemical reaction and bio-labeling. Nanosilver (Ag-NP) has both antibacterial and antiviral activity. Yet, the knowledge about the systemic toxicity of nanosilver is relatively limited. The aim of work: To evaluate the potential toxicity of small size 10nm silver nanoparticles using two different doses (0.1 ml and 0.4 ml) focusing on the ultrastructural changes occurring in mice hepatocytes.     The methods: This study was performed using three groups of mice. The animals of the first group were given a daily intravenous injection of 0.1 ml of silver nanoparticles for 28 consecutive days. The second group was treated with 0.4 ml of silver nanoparticles for 28 consecutive days. The third group served as a control group in which the animals did not receive any vehicle. The study was focused on the ultrastructure of the liver.     The results: Ultrastructure observations of liver cells of miceTreated with any of the two doses (0.1 and 0.4 ml) of 10 nm Ag-NP indicated severe accumulation of dark deposits of Ag-NP in the cytoplasm and the cell organelles.     Conclusion: Our study revealed that nanosilver used in doses of 0.1 and 0.4 ml led to deposits in the cells and induced damage of cell components especially the nucleus, mitochondria and chromatin.