In this work, a functional graphene oxide-iron oxide-silver (GO-Fe3O4-Ag) ternary nanocomposite was synthesized by using one-pot hydrothermal treatments of mixture solutions of silver nitrate (AgNO3), ferrous chloride tetrahydrate (FeCl2 4H2O), polyvinylpyrrolidone (PVP), graphene oxide (GO), and ammonium hydroxide solution (NH4OH). The systematic effects of synthesis conditions on the microstructure and formation of binary and ternary composite systems were studied. Importantly, high-crystalline GO-Fe3O4-Ag ternary nanomaterials with average sizes of Fe3O4 particles ~16 nm and of Ag particles ~20 nm were obtained at optimized conditions (125 °C, 2.5 mM of AgNO3 and 5 mL of NH4OH). Magnetic analysis indicated that the saturated magnetization value of Fe3O4-Ag binary composite sample (~73.1 emu/g) was improved as compared with pure Fe3O4 nanoparticles (~60.6 emu/g), while this of GO-Fe3O4-Ag ternary composite sample was about 57.3 emu/g. With exhibited advantages of low-cost, high purity and short synthesis time, the hydrothermal-synthesized GO-Fe3O4-Ag ternary nanocomposite can be a promising candidate for advanced environmental catalyst and biomedical applications.