  We examine the thermodynamic and thermoelectric properties in the stripe
phase of high-Tc cuprates, by using the finite-temperature Lanczos technique
for the t-J model with a potential that stabilizes vertical charge stripes.
When the stripe potential is turned on, the entropy is suppressed as a
consequence of the formation of one-dimensional charge stripes accompanied by
an enhancement of antiferromagnetic spin correlation in the spin domains. The
stripe formation leads also to weak temperature dependence of the chemical
potential, leading to the suppression of the thermoelectric power. The
suppression of the entropy and thermoelectric power is consistent with
experimental data in the stripe phase of La_{1.6-x}Nd_{0.4}Sr_xCuO_4.
