Abstract
We report the results of the first search for the decay B-s(0) -> eta'K-S(0) using 121.4 fb(-1) of data collected at the gamma(55) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We observe no signal and set a 90% confidence-level upper limit of 8.16 x 10(-6) on the B-s(0) -> eta'K-s(0) branching fraction.