In spite of importance of IT deployment, nowadays in many organizations we are witness of appearing problems related to dissatisfaction of business needs due to high investment in the field of IT. The fervent debate concerning IT productivity–or lack of such productivity- named productivity paradox persuade us to survey relationship between IT–business alignment and business performance. The purpose of this research is to investigate whether IT-business alignment could have a decisive influence on their performance in IT-base firms by adopting a contingency theory perspective and operationalizing the fit systemically. Also to measure organizational performance, we adopt BSC framework which is not applied in this matter yet. Finally, this paper will explore the notion that alignment between business and IT is the key to achieving improved business performance through IT.