Nitrogen-doped carbon nanofibers (CNFs) were prepared by an electrospinning method, this followed by a hydrothermal reaction or nitrogen plasma treatment to obtain electrode for non-enzymatic amperometric sensing of H2O2. The hydrothermally treated electrode performs better. Its electrochemical surface is 3.7 x 10(-3) mA cm(-2), which is larger than that of a nitrogen plasma treated electrode (8.9 x 10(-4)) or a non-doped CNF (2.45 x 10(-4) mA cm(-2)). The hydrothermally treated CNF with rough surface and a complex profile with doped N has a higher sensitivity (357 mu Aa (TM) mM(-1)a (TM) cm(-2)), a lower detection limit (0.62 mu M), and a wider linear range (0.01-0.71 mM) than N-CNFP at a working potential of -0.4 V (vs. Ag/AgCl). The electrode gave high recoveries when applied to the analysis of milk samples spiked with H2O2.