Abstract In this study, we have performed non-equilibrium molecular dynamics simulation (NEMD) to the interface thermal transport in silicene/stanene hetero-structures, which include the effect of structure size, temperature and defects on the thermal conductance G. The results show that G increases with the temperature significantly, while almost keep constant with the variable of the size of structure. The vacancy defects will lead to the decrease of saturated thermal conductance compared with the defect-free one, which is ascribed to the enhancement of phonon inversion process and the scattering concentration of the phonons. In particular, a singularity point of thermal conductance is found when a single vacancy defect is set in the interface of stanene with the vacancy defect moving. Our result indicates that the thermal conductance of silicene/stanene hetero-structures present remarkable properties (low size dependence and singularities exist as defects move) and are promising for applications of the low dimensional silicene/stanene nanostructure based thermal and nanoelectronic devices.