We report results from a search for the decay B-s(0) -> eta eta using 121.4 fb(-1) of data collected at the Upsilon(5S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We do not observe any signal and set an upper limit on the branching fraction of 14.3 x 10(-5) at 90% confidence level.
This result represents a significant improvement over the previous most stringent limit.