Layered two-dimension (2D) materials, such as layered graphene, hexagonal boron-nitride, etc., hold great promise for future electronic, optical, thermal devices and beyond, underpinning which the predictability, stability and reliability of their mechanical behavior are the fundamental prerequisites. Despite this, due to the layered crystal lattice structure, high anisotropy, and the decoupling between intralayer stiffness and out-of-plane bending rigidity, a general continuous mechanics model of such materials is still missing. Starting from an effective layer-by-layer model, we propose a Continuous Layered 2D Material Model (CL2M), which is transversely isotropic featuring surface elasticity and independent bulk bending modulus. The surface elasticity emerges from the layered nature of layered 2D material crystal lattice, unlike the standard surface elasticity model for 3D lattice. The independent bulk bending modulus emerges from monolayer decoupled bending rigidity, with a clear and well-defined physical meaning. Based on our model, the behavior of typical simplified cases, including beams, plates and indentation of half space, are presented to showcase its ability and applicability. It is found that the bending behavior of both layered 2D material beams and plates can be characterized by several dimensionless parameters. A size effect on the indentation of layered 2D materials emerging from pure elasticity is identified, distinct from the already well-recognized size effect caused by plasticity. In addition, we emphasize the crucial role played by the surface effect and curvature effect in governing the mechanical behavior of layered 2D materials. Our work not only provides guidance for the studies and applications of layered 2D materials, but also sheds lights on the physical origin of the strain gradient, high-ordered moduli and couple stress in the high-ordered continuum mechanics theories.