Electrochemical hydrogen evolution reaction (HER) from water splitting is a promising way to promote the utilization of renewable energy. Designing and fabricating electrocatalysts with low cost, high catalytic activity and robust stability is desirable. In response, we prepared carbon shells encapsulating ultrafine beta-Mo2C nanoparticles with N and P dual-doping as advanced electrocatalyst used for HER in both acidic and alkaline mediums. This paper gives a discussion on element doping and porosity which have influence on the HER performance. As introducing heteroatoms into carbon matrix to create active sites and enhance electron transfer capacity, the as-prepared electrocatalyst exhibits high catalytic activity with low overpotential of 117 mV and 121 mV to achieve current density of 10 mA cm(-2) in acidic and alkaline solutions. Due to the strategy of carbon shells encapsulating, the catalyst presents robust stability for a long time at various applied potential. Furthermore, the design idea of using multiple strategies preparing catalysts may serve some inspiration to fabricate advanced electrocatalysts. (C) 2019 Elsevier Inc. All rights reserved.