SrCe).95Yb0.05O3-a (SCYB) sinters were prepared, whose density was in the range of 95.8-96.5% of the theoretical value. Its proton transference number varies linearly from 0.97 to 0.89 as temperature increases from 773 to 1123 K. Probes with Ca/CaH2 reference were tested in a wide range of temperatures for a long time for sensing hydrogen content in molten A1. The results of TG analysis indicate that Sr in excess in SCYB improved the stability of the solid electrolyte under a strong reducing condition.