The physico-chemical characteristics of cement pastes are studied in absence and presence of nano metakaolin (NMK), silica fume (SF) and cement kiln dust (CKD); (2, 4, 6, 8 and 10%)which immersed in 5%MgSO₄. These characteristics are investigated at different hydration times up to 180 days via determination of the compressive strength and combined water content. In addition, the phase composition of the formed hydrates is investigated through X-ray diffraction analysis. The IR spectra of  hardened cement pastes are also recorded. The results indicated that the presence of nano metakaolin accelerates the hydration of the pastes that exhibit higher compressive strength than the ordinary Portland cement alone. The optimum mixes are containing 10% NMK and mix containing 8% NMK and 2%SF.