A novel kind of hybrid nanoparticles, Fe₃O₄@poly(ε-caprolactone)-carbazole, i.e. Fe₃O₄@PCL-carbazole, was synthesized via surface-initiated ring-opening polymerization (ROP) from glycolic acid — functionalized Fe₃O₄, and N, N′-Dicyclohexylcarbodiimide (DCC) was used to combine carbazyl group to the hydroxyl group at the end of PCL. The organic polymers as the shell were obtained with a narrow molecular weight distribution. Superparamagnetism and fluorescence of the nanoparticles were investigated by vibrating sample magnetometry (VSM) and fluorescence spectra. The study of the release of model drug progesterone from the hybrid nanoparticles indicated that the drug was released slowly and steady-going. Combined with the advantage of superparamagnetism, biodegradability, biocompatibility and fluorescence, the hybrid nanoparticles could be used as novel potential carriers and applied extensively in targeted drug delivery and release.