  The superconducting gap modulation is investigated in the presence of a weak
stripe structure, using the Bogoliubov-de Gennes theory on the two-dimensional
Hubbard model with nearest-neighbor site pairing interaction. We calculate the
local density of states and discuss the recently observed scanning tunneling
spectroscopy spectra with four lattice periodicity on Bi_2 Sr_2 Ca Cu_2
O_{8+delta} We also consider the spectral weight in the reciprocal space, where
the Fermi surface and the superconducting gap are modulated by the band folding
effect of the stripe structure.
