Tuning the multiphysical properties of advanced materials are of critical importance for developing the next generation of adaptable multifunctional metamaterials. This study demonstrates the tunability of thermo-mechanical properties of graphene sheets by inspiring from kirigami mechanical metamaterials. The theoretical investigation, multiscale simulation, and experimentation demonstrate that the thermo-mechanical properties of nano-architected kirigami metamaterials can be controlled by altering geometrical parameters and introducing hierarchical cutting patterns. The thermal conductivity of graphene metamaterials can be also regulated by an external mechanical tension. We develop closed-form formulations for predicting the mechanical behavior of kirigami graphene sheets. Molecular dynamics and finite element simulations are conducted to evaluate theoretical predictions. By analyzing and comparing the results from atomistic and continuum-based simulations, the effect of length scale on the thermo-mechanical properties is explored. We realize that the stress-strain response, thermal conductivity, and buckling-induced 3D patterns of nano-architected graphenes can be programmed by a rational design of kirigami building blocks, nano-architectural hierarchy, and heterogeneous material design approach.