The multiple tube preparation of a silica membrane using a porous α-alumina tube as a support tube was carried out by chemical vapor deposition (CVD) to scale up the membrane reactor. A porous alumina tube with a pore size of 100 nm was modified by chemical vapor deposition using tetraethoxysilane as an Si source. The single-component permeance of H2 and N2 in the prepared silica membrane that was achieved by a multiple tube membrane preparation system was measured at 300-600 ℃. Hydrogen permeance of the modified membrane at a permeation temperature of 600 ℃ was 5×10^(-8) mol·Pa^(-1)·m^(-2)·s^(-1). H2/N2 selectivity at 600 ℃ was about 32. It was confirmed that permeance of H2 and N2 and the selectivity for H2 to N2 in the prepared silica membrane by the multiple tube membrane preparation system had almost the same value compared to those of the silica membrane prepared by the single-tube system.