Intrinsic activity modifying of electrocatalysts is crucial to realizing the excellent catalytic performance towards hydrogen evolution reaction. Herein, we demonstrate a highly efficient electrocatalyst based on heterogeneous cobalt phosphides nanoparticles. The ultra fine size of the as-prepared catalyst (similar to 5 nm) ensures the efficient extension of active sites. Furthermore, the incorporation of orthorhombic CoP and Co2P contributes to the improvement of the inherent catalytic property. As a consequence, the as-prepared heterogeneous cobalt phosphides nanoparticles supported on carbon cloth exhibit impressive electrocatalytic activity, which only acquire a small overpotential of 90 mV at a current density of 10 mA cm(-2), and present a low Tafel slope (67.9 mV dec(-1)), a large exchange current density (0.58 mA cm(-2)) as well as good durability. Therefore, this work provides a favorable guidance for exploring executable strategies to improve catalyst activity. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.