Prussian blue (PB)/multiwalled carbon nanotubes (MWNTs)-modified glass carbon (GC) electrode (PB/MWNTs/GC electrode) was chemically fabricated for the first time, using a sequential deposition-based method. PB crystallites are observed to be finely attached to the MWNTs of the prepared PB/MWNTs/GC electrode in which the MWNTs not only act as a carrier of PB but also as a modifier with catalytic function. Cyclic voltammetry (CV) studies demonstrate that the modified electrode has outstanding stability. The prepared PB/MWNTs/GC electrode can be used to determine the concentration of H2O2 in solution.