MoS2-carbon composites which with different morphologies were synthesized by hydrothermal method and tested with respect to their application in hydrogen evolution reaction (HER). Their performances were compared to evaluate how the morphology influence HER. The obtained results showed that the composite containing amorphous MoS2 showed higher activity than composite which contains crystalline MoS2. The catalytic activity of composite was highly correlated to its active surface area which was controlled by the morphology. In addition, compared with composite which contains amorphous MoS2, the composite containing crystalline MoS2 showed higher durability in the long-term operation. However, in acidic and alkaline environments, the stability of composite containing amorphous MoS2 is better than which containing crystalline MoS2. The impedance measurements suggested that the high catalytic activity of the composite stems from the synergistic effect of MoS2 and carbon materials. The enhanced understanding of these highly active hydrogen evolution catalysts can facilitate the development of economical electrochemical hydrogen production systems. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.