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In this talk, an atomic-continuum coupled model and a recursively adaptive multiscale algorithm for thermo-mechanical behavior of materials is systematically presented[2].First, an atomistic-continuum coupled model for thermo-mechanics behavior of materials in micro-nano scale range is discussed.The atomic motion is decomposed into "structure deformations" and "thermal vibrations".For "structure deformations", the non-local stress-strain relationship in nano-micro scales is defined by means of the representative volume element composed from a cluster of atoms, and the conception of deformation environment [1] as well.The energy transportation rate and free energy of inhomogeneous atom cluster are obtained.Then the free energy density is analyzed by the deformation environment function in the extended representative volume element, the entropy density and internal energy density as well.And then the atomic-continuum equations are constructed based on momentum conservation and energy conservation.The non-locality of atomistic interactions is built into the thermo-mechanical constitutive equations.As the deformation of atomic lattice is homogeneous, the model naturally leads to Cauchy-Born model, and the high order strain gradient models can be also obtained by some high order deformation approximation.The expressions corresponding to macro thermo-mechanical constitutive parameters are also given.