Abstract:IT -business alignment has always been a hot topic in the field of information systems research. On the one hand, many scholars regard the conclusion that IT – business alignment can improve business performance as the underlying assumptions directly. On the other hand, some studies put forward “alignment paradox”, thinking that IT - business alignment can make the enterprise come into “rigid trap”. So what the relationship is between IT-business alignment and business performance? This paper uses meta-analysis to test the relationship between them quantitatively and explores the boundary conditions. Analysis results show that IT – business alignment influence business performance signally(r=0.398), in the way of measuring method, data investigation method and research time. The influence of the industry, enterprise scale is unclear and still needs to further research.