This study applies NMR, SRA, MIP, SEM and electric resistance tests to examine the microstructure of the composite materials of nano concrete. The test results show that owing to the pozzolanic reaction activated by the nanopowders, the CaOH2 content within the composite materials is decreasing, filling the capillary and gel pores. This way, the microstructure of the composite materials is transformed in its arrangement, which makes concrete much more well-mixed and densified, enhancing the compressive strength. The permeability is cut down as well. In conclusion, it ends in much better durability.