In order to improve the mechanical strength and durability of cement based artificial stone, nano graphene oxide(NGO) was mixed into it. The effects of NGO content on the setting time, fluidity, mechanical properties and durability of low water to binder ratio cement paste and cement mortar were studied. The micro analysis methods of hydration heat, X ray diffractometer(XRD), thermos gravimetric differential scanning calorimetry(TG DSC), scanning electron microscope(SEM) and mercury intrusion porosimetry(MIP) were used to analyze the mechanism of NGO. The results show that the compressive strength of cement mortar with 002% NGO can be significantly improved by 2095% at 28d, and the chloride diffusion coefficient can be reduced to 029×10-12m2/s compared with the control group without NGO. At the same time, it can also promote the early hydration of cement paste, reduce autogenous shrinkage, refine pore size, thus improving the durability and mechanical properties of cement based artificial stone.