Abstract: Background and Objective: Gold nanoparticles (AuNPs) widely had been used in the medicine and industries, but the safety of the gold NPs exposure remains unclear. The aim of the present study was to evaluate the toxic effects of thioacetamide (TAA) (300 μg kg–1) and gold nanoparticles (AuNPs) (300 μg kg–1) in the organs of mice. Materials and Methods: The mice were treated with fixed doses of gold nanoparticles and thioacetamide every day for 5 days. In the blood values of WBCs, RBCs, neutrophils and other blood components were changed as compared to normal values after the treatment in mice groups (1-3 and 4). Results: Results indicated that the thioacetamide caused the hepatic damage and caused down regulation of checkpoint gene p53 and also decreased the expression level of apoptotic caspase protein (Casp3, Casp8 and Casp9) which was measured by qRT-PCR. While the gold NPs upregulated the p53 gene which is responsible for the DNA repair and also known as the checkpoint of the cell cycle. The gold nanoparticles were activated and up-regulated the caspase-3, caspase-8 and caspase-9 and induced apoptosis. Conclusion: It was concluded that gold nanoparticles activated the apoptotic genes which had the ability to kill the cancer cell. However, further studies are recommended to have better insight.