Two-dimensional (2D) materials, with atomically thin van der Waals layered structure, exhibit both novel physical properties and promising applications in electronic, optoelectronic and energy-harvesting devices. Currently 2D material research has become one of the most exciting topics in physics, engineering and material communities due to the easy preparation processes, rich species and unique properties. Among all the unique properties of 2D materials, the ability to electrically tune the electronic, optical and even magnetic properties at a mild electrostatic doping offers us numerous possibilities for investigating electro-matter interactions and novel device applications. Here, we review the electrically tunable physical properties of several interesting 2D materials as well as the relevant applications on devices utilizing these unique properties. The electrically tunable valley properties of 2D materials and the recent discovered 2D magnetism are also included. (C) 2019 Elsevier Ltd. All rights reserved.