Effect of hydrogen on the flow behavior of a TiAl based alloy during plane strain compression at temperatures of 1150 and 1200 degrees C was investigated in this paper. The results showed that hydrogen obviously softened the alloy and had significant effects on the texture evolution. Hydrogen decreased the number of sharp yield points and hindered the occurrence of Portevin-Le Chatelier effect, which decreased plastic instability of the alloy during plane strain compression. Hydrogen enhanced textures related to gamma-phase recrystallization and twinning, as well as alpha(2)-phase pyramidal texture component. Additionally, weak alpha(2)-phase transverse texture component {11-20}< 0001 > was present in the hydrogenated samples, and the occurrence of such texture was mainly attributed to hydrogen increased B2 phase. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.