The electrocatalytic hydrogen evolution reaction (HER) is one of the core components of energy conversions. The chemical-physical properties and morphological structures of electrocatalysts are the main factors that determine the HER performance. Thus, the rational design of efficient electrocatalysts is essentially required. A new heteronanostructured system is proposed, which comprises MoS2 nanoparticles (MoS2 NPs) coupled to SnS2 ultrathin nanosheets (SnS2 NS) and operates as an efficient HER electrocatalyst. Advanced spectroscopic techniques are applied to confirm formation of heteronanostructure and occurred electron modulation of MoS2 NPs/SnS2 NS. Surprisingly, the MoS2 NPs/SnS2 NS electrocatalyst is highly efficient for HER with a low overpotential (similar to 0.249 Vat the current density of 10 mA cm(-2)), small Tafel slope (similar to 42.1 mV decade(-1)) and excellent electrocatalytical stability. (C) 2018 Elsevier Inc. All rights reserved.