In prior research, the formation of alliances is an important issue of strategic alliance, and alliance motivations are important factors affecting alliance formation. Prior research has led to valuable insights on the alliance motivations, and contributed to full exploration, like transaction cost theory and resource dependence theory. Truly, alliance motivation is an important factor affecting alliance formation, however, is motivation the only one to cause the formation alliances? Is there no any motivation once the business wouldn’t Join alliances? In order to discuss the alliance formation completely, this article integrates alliance motivation theory and social relationship theory in the perspective of the cost-benefit decision theory. This research finds: alliance motivation is regarded as expected benefit of alliance formation. Although expected benefit have positive effects on the formation of alliances, alliance formation outcomes is the assessment of expected benefit and perceived cost. The negative effect of perceived cost will cause the business unwilling to join the strategic alliance. Furthermore, how to reduce perceived cost to promote the business joining strategic alliance, social relationship theory plays an important role. This study attempted to build up the research framework of the formation of alliances and provide the practices suggestions about forming alliance.
