In this research, the Compressive Strength (CS) and Thickening Time (TT) of oil well cement with different Metakaolin (MK) dosages was evaluated in the presence of Nanoclay (NC). The experiments followed a randomized BoxBehnken Design (BBD) using 5 - 15 wt. % MK by weight of cement and 5-15 wt. % NC by weight of MK. The CS and TT were assessed and optimized using Response Surface Methodology (RSM). The results show that CS increases linearly with NC and hyperbolically with MK. Cement slurries with 5–15 wt.% NC shorten TT by about 35 minutes in the presence of 5 wt.% MK. A TT reduction of 103 minutes was recorded when MK was increased to 15 wt.% in the slurry with 5wt.% NC. At the optimum conditions with 10.78 wt. % MK and 13.73 wt. % NC, CS and TT were 3029±2.65 psi and 410±1.25 minutes, respectively.