The SrZr
1-xY
xO
3-α of proton conductor was prepared by normal sintering and SPS (spark plasma sintering) methods in order to separate pure hydrogen gas from H
2-containing mixed gases in high temperature range. The SrZr
1-xY
xO
3-α has high proton conductivity under H
2 gas atmosphere from 973 K to 1273 K. In this hydrogen separation system, hydrogen is oxidized to proton at the anode, and proton is reduced to hydrogen at the cathode using proton conductor by electrochemical method. Proton conductors SrZr
0.9Y
0.1O
3-α obtained by normal sintering at 1580°C for 10 h and SPS at 1500°C for 3 min were found to be single phase of perovskite structure. Furthermore, the crystal structure of SrZr
0.9Y
0.1O
3-α was chemically stable under H
2 and CO
2 gases atmosphere. Relative densities of SrZr
0.9Y
0.1O
3-α obtained by SPS at 1400 and 1500°C were over 95 %. Furthermore, the relative density increased with sintering temperature and time of SPS. The proton conductivity of SrZr
0.9Y
0.1O
3-α of SPS increased with sintering temperature, and was higher than one of normal sintering under wet 10 % H
2 and Ar gases atmosphere. From the measurement of EMF (electromotive force) of hydrogen concentration cell at 800°C, the ionic transport number of SrZr
0.9Y
0.1O
3-α of SPS at 1400°C for 5 min was about 1, and the electron conductivity was considerably low.
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