Human cytomegalovirus (HCMV) infection in infants cause severe diseasessuch as neonata hepatitis, However, the single-cell dimensiona description otthe immune cel alteration during the first virus exposure process in infantsremains poorly understood. The hepatocytes play an essential role in metabolichomeostasis and detoxification, The Concomitant Effects of CMV infection oriver lipid metabolism in infants are still unclear. Here, using single-cell RNAsequencing, we found MCMV can infect most cell types of infant mice liverchanging the number of immune cells, MCMV infection increases proliferatincsubset of Nos2+CD8 effectorcells and amonocytes，which may plalimportant roles in the early anti-viral process. Furthermore, MCMV infectiorsubvert the protein expression profile of lipid metabolism in hepatocytesOverall, our data provide insights as to how the immune system response toMCMY infection during the early stage of infection, and the impact of infectionon lipid metabolism in infant mice hepatocvtes.