The effect of information system on decision making is a central concern in the field of information system (IS). Information systems form the backbone of any business process integration and the main objective of information systems is helping decision makers by providing accurate and time based information helping them in making the right decisions in turbulent environment. The present study has been performed to examine the impact of using management information systems (MIS) and conceptual dimensions of information quality on the quality of managerial decisions in public organizations in Iran. Sample of the study was 250 of the managers from 17 public organizations that were chosen randomly and data was collected on 2015. Using artificial neural networks (ANN) analysis results show that MIS and conceptual dimensions of information quality have a positive effect on quality of managerial decisions and this effect is stronger when MIS and conceptual dimensions of information quality are merged.