  We investigate the parametric electron pumping of a double barrier structure
in the presence of a superconducting lead. The parametric pumping is
facilitated by cyclic variation of the barrier heights $x_1$ and $x_2$ of the
barriers. In the weak coupling regime, there exists a resonance line in the
parameter space $(x_1,x_2)$ so that the energy of the quasi-bound state is in
line with the incoming Fermi energy. Levinson et al found recently that the
pumped charge for each pumping cycle is quantized with $Q=2e$ for normal
structure when the pumping contour encircles the resonance line. In the
presence of a superconducting lead, we find that the pumped charge is quantized
with the value $2e$.
