Multifunctional nanocarriers based on Fe3O4@C@Ag hybrid nanospheres with adiameter of 200 nm were fabricated by a facile and green method. Silver (Ag) nanoparticles weredeposited onto the surface of the Fe3O4@C nanospheres in dimethyl formamide (DMF) solutionby reducing silver nitrate (AgNO3) with glucose. The nanocarriers of doxorubicin (DOX) with aloading content of 997 mg/g and near-infrared (NIR) light-responsive drug delivery wererealized. Strong fluorescence can be observed in cell nucleus due to the presence of DOX afterirradiated by NIR, and most cells are in the state of apoptosis, which indicates NIR-regulateddrug release was realized. Moreover, measurements show that the nanocarriers could also be used as diagnostic agents, including magnetic resonance imaging (MRI) contrast agents andfluorescent probes. The combination of synergistic NIR controlled drug release and multimodalimaging of MRI and two-photon fluorescence (TPF) could lead to a potential multifunctionalsystem for biomedical diagnosis and therapy.