<p>Oil production from the matured oil fields has always been a challenge for reservoir and production engineers. An attempt to understand the role of different clays, hydrophilic (HP) and hydrophobic (HB) on the various reservoir property such as wettability, surfactant adsorption, permeability reduction and oil mobilization potential has been explored. The effect of different clays on the wettability alteration was investigated along with the impact of pH, salinity and time. Moreover, quantification of adsorption losses in the presence of different clay was also examined, and data thus obtained were fitted on various isotherm models. Variation in pH of the system indicated that the extreme values of pH prefer water-wetting surface. On the other hand, a high percentage of HP increased the amount of surfactant loss from 8.71 to 21.96&#xa0;mg/g when 100% was clay was used for adsorption whereas the same for HB was 16.52&#xa0;mg/g. HP reduced the original permeability of the porous column by 34% whereas the same for HB was only 10%. Flooding experimental results indicate the presence of clay content can hamper oil production. Almost 70% (47% secondary, 23% tertiary) of the oil was recovered via surfactant polymer flooding from the sand pack having zero clay content which reduced up to 49% (33% secondary, 16% tertiary) for HP and 57% (39% secondary, 18% tertiary) for HB when 100% of respective clays were used to prepare the porous column used for flooding experiment. Furthermore, the return permeability studies suggested that the presence of hydrophilic and hydrophobic clays reduced the original permeability 34 and 10%, respectively. It can be inferred from the results that the presence of clay content can preferentially water-wet the surface but at the same time damage the reservoir and increase the surfactant loss.</p>