The effect of basement’s upper surface morphology on the accommodation development is investigated in this study, through a case study from the Asmari Formation in Dezful Embayment and Abadan Plain.  Considering the depth of the basement’s upper surface, position of the studying formation’s bounding surfaces, its thickness and total thickness of basin fill sediments are calculated.  Based on the available data from previous researches and data extracted from more than 200 drilled oil wells in the studied area, the maps of basement surface, the Asmari Formation bounding surfaces, isopach maps of the Asmari Formation and total basin fill deposits are created. Results from this study shows the minimum and maximum depth of the basement’s upper surface 7,000 and 15,000 meters respectively. The deepest level of the surface is in the north Dezful Embayment, while the shallowest level in the southern Dezful and Abadan plain. The maps of the formations bounding surfaces well correlates with the basement’s upper surface map, especially in the north Dezful embayment area. Similar results are achived from the correlation of created isopach maps with that of basement’s top. However, slight discrepancy in the correlations is observed in the south Dezful embayment. Results of present study clearly show that development of accommodation space of the Asmari Formation in the north Dezful embayment and Abadan plain was mainly affected by the basement upper surface during different sedimentation periods. The accommodation space in the southern Dezful embayment was most likely affected from the basement faults’ actvities. Highest rate of sediment supply was recorded in the middle part of the north Dezful embayment.