A new type of one-dimensional bifunctional CNTs/Fe3O4 @ SiO2 (FITC) nanohybrids with both magnetic and fluorescent properties were fabricated by a polyol method combined with stöber method. The CNTs/Fe3O4 @ SiO2 (FITC) nanohybrids exhibit strong and stable photoluminescence emission at about 520 nm, display superparamagenetic behavior with high saturation magnetization and possess MRI function at room temperature. All these properties make the CNTs/Fe3O4 @ SiO2 (FITC) nanohybrids a potential candidate for biomedical agent such as MRI contrast agent, cells labelling, in-vivo image and drug deliver for cancer diagnosis and treatment.