Electrocatalysts play a vital role in electrochemical water-splitting for hydrogen production. However, searching for low-cost and earth-abundant electrocatalysts remains a challenge. In this study, we report the synthesis of mesoporous molybdenum phosphide hemispheres as electrocatalysts and their direct growth on a carbon cloth (MoP-HS@CC) to create a self-supported electrode for efficient hydrogen evolution. The obtained MoP-HS@CC was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and nitrogen adsorption–desorption. MoP-HS@CC not only has a large surface area, it also possesses rich porosity. In addition, as a binder-free electrode for hydrogen evolution, MoP-HS@CC exhibits a low onset overpotential of 30 mV, a small Tafel slope of 61 mV dec⁻¹, and a large exchange current density of 0.438 mA cm⁻² in acidic electrolytes. It affords current densities of 10 and 100 mA cm⁻² at overpotentials of 87 and 195 mV, respectively. Moreover, MoP-HS@CC shows a strong tolerance to working environment both in acidic and alkaline conditions. This study essentially offers a simple and viable strategy for preparing highly efficient and flexible electrodes on a large-scale for electrochemical water-splitting technology.