Montmorillonite (Mt) is a kind of 2:1 type layered phyllosilicate mineral with nanoscale structure, large surface area, high cation exchange capacity and excellent adsorption capacity. By virtue of such unique properties, many scholars have paid much attention to the further modification of Mt-based two-dimensional (2D) functional composite materials, such as Mt-metal hydroxides and Mt-carbon composites. In this review, we focus on two typical Mt-2D nanocomposite: Mt@layered double hydroxide (Mt@LDH) and Mt@graphene (Mt@GR) and their fabrication strategies, as well as their important applications in pollution adsorption, medical antibacterial, film thermal conduction and flame-retardant. In principle, the prospective trend of the composite preparation of Mt-2D nancomposites and promising fields are well addressed.