Herein, we present molecular nanoparticles of ferric-tannic complexes (so called ferric-tannic nanoparticles, FT NPs) used to enhance the MRI signal in the early stage of hepatocarcinoma. FT NPs were found to accumulate in the hepatic parenchyma without tumor nodules of Wistar rats in which hepatocarcinogenicity had been induced using diethylnitrosamine (DEN). The MRI enhancement and accumulation of FT NPs were clearly observed in the early phase of hepatocarcinogenicity, which was possibly modulated by various solute carrier family members present in the entire hepatic parenchyma of the DEN-induced rats. These findings suggest that MRI with FT NPs is promising for the assessment of the early stage of hepatocarcinoma.