The main purpose of conducting this research is to investigate empirically the role and importance of data warehouse (DW) in enhancing the effectiveness of decision-making. It is believed and assumed that meaningful and significant information can be acquired from DW which provides valuable knowledge to support business process and decision-making. A mail questionnaire survey was regarded as the appropriate method for gathering data. The questionnaire was developed based on the findings from related literature and other related research questionnaires. All the firms (277), which were listed on Amman Stock Exchange (ASE), at the time of data collection, were selected. The researchers arrived at scores of significant and remarkable results regarding DW and its role in enhancing the process of decision-making. The survey’s findings showed that the percentage of implementing DW in the Jordanian firms involved is 35 %. In general, the respondents had a positive attitude towards the implementation of DW.