Tsunami run-up wave has been hypothesized as non-Newtonian fluid due to the presence of sediment and debris in its body. This paper assesses the rheology of run-up wave based on the established flow and viscosity curves. Soil sampling was conducted at shoreline of Kuala Teriang and Kota Kuala Muda, Kedah, Malaysia. Investigation on the geologic layers at four different trenches i.e. two from each sites showed that positive indication of tsunami deposits exist at Kuala Teriang. Observation at Kota Kuala Muda was rather challenging due to factors such non-discrepant grain size and sediment type between native and tsunami deposits, inadequate post sedimentation to preserve the tsunami soil, and weathering effect. Rheology experiment conducted used four different mixtures with varying volumetric concentration of tsunami fine sediment i.e. 10, 20, 30 and 40. Results showed that all mixture exhibit non-Newtonian Bingham pseudoplastic behavior with threshold limit ranging from 0.0328 to 131.2 Pa. © 2016 Taylor & Francis Group, London.