In this article, a numerical model has been developed in order to examine the effect of rigid and flexible footings vertically loaded on the behavior of oil-contaminated soil layers by black oil with respect of natural soil strata characteristics. The analyses have included modeling the spread rigid and flexible footings founded on natural soil have been collected from south of Iraq, and contaminated specimens of 10% by weight. The thickness of the contaminated layer (D) has been gradually increased from 1.0 m to 4.0 m from footing base. Three footing width (B), 1.0m, 2.0m and 3.0 m have been simulated in the study. The finite element package PLAXIS 3D has been adopted to simulate the oil contamination problem and to relate the performance of a spread footing supported on natural soil and contaminated soil with different footing width (B) and thickness of contamination layer (D). The outcomes have found out that the vertical ground movement can be reduced by minimum thickness of soil contamination layer. The vertical ground movement has been reduced because of soil contamination when the contamination depth (D) is less than or equal footing width (B) with respect to vertical ground movement of natural soil in case of two types of footing. The behavior of rigid footing has showed more lessening in vertical ground movement as contamination layer thickness (D) 1.0m for all the footing widths.