Nucleosynthesis in supernova explosions is strongly dependent on the gravitational mass of the proto-neutron star. So far, the models of neutrino-driven winds from very massive (M～ 2.0solar mass) and compact (R～10 km) neutron star have been proved to get a successful r-process abundance pattern. This is because a short expansion time is required to obtain a high neutron-to-seed ratio at a moderate entropy. However, such a large mass is sometimes criticized from observational facts on a neutron star mass. In this paper, we study the effects of the outer boundary conditions of neutrino-driven winds on the r-process nucleosynthesis. The boundary condition is set as a pressure upon the wind just behind the shock wall. By varying this boundary pressure, we obtain various asymptotic thermal temperature of the neutrino-driven winds. We find that the asymptotic temperature slightly lower than those ever used in the numerical simulations of the winds can lead to the r-process abundance pattern in a reasonable agreement with the solar system r-process abundance even by adopting the typical proto-neutron star mass 1.4solar mass.
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