The paper presents experimental evidence of continuous detonation in a rotating detonation rocket engine (RDRE) powered by H-2/O-2 propellants. High-speed chemiluminescence imaging is used to characterize the detonation wave dynamics by introducing a tracer in the hydrogen fuel flow. The results show continuous five-wave co-rotating detonations at various equivalence ratios and flow rates demonstrating the potential for H-2/O-2 propellant based RDREs for upper-stage rocket engines. (C) 2019 The Combustion Institute. Published by Elsevier Inc. All rights reserved.