Experimental and numerical study is conducted to investigate the performance of a horizontal well during waterflooding of a sandstone outcrop. Three different well configurations, viz., vertical injection-vertical production (VI-VP), vertical injection-top horizontal production (VI-HPT), and vertical injection-bottom horizontal production (VI-HPB) are considered. The commercial simulator, ECLIPSE, is used for the numerical study, and history matching technique has been used to obtain the relative permeability characteristic of the sandstone outcrop. The results show that VI-HPT configuration provides nearly the same oil recovery as that of VI-VP pattern but in less time. It is also observed that the VI-HPB well pattern provides the lowest breakthrough and final oil recovery, whereas the VI-VP pattern provides the highest breakthrough recovery. Moreover, the post-breakthrough recovery by horizontal production wells is higher than that of vertical production well. The experimental and numerical simulation results are found to be in good agreement.