Supply chain integration (SCI) is defined as the strategic collaboration of the manufacturer with its supply chain partners and the degree of collaborative management in both intraorganizational (i.e., among departments) and interorganizational (i.e., among suppliers and customers) processes (Flynn et al. 2010; Zhao et al. 2011). Most previous studies on the relationship among information technology (IT), SCI, and firm performance have been constantly increasing. Most of the previous studies argued that the correlation between IT and firm performance (Albadvi et al. 2007; Carr and Kaynak 2007; Liang et al. 2010), and that between SCI and firm performance (Boyer and Lewis 2002; Prajogo and Olhager 2012; Cao and Zhang 2011; Khanchanapong et al. 2014) were positive. Also, there exist multiple studies, which argued that IT played a role of an enabler of SCI (Fawcett et al. 2011; Wu et al. 2014). Nevertheless, there remain many research areas that previous studies could not address satisfactorily. First, while many previous studies dealt with the business utilizing IT in managing supply chain, in-depth studies on the relationship between the use of IT and firm performance from the process-oriented perspective in the area of supply chain management are rare (Tippins and Sohi 2003; Wu et al. 2006; Vijayasarathy 2010; Qrunfleh and Tarafdar 2014; Pavlou and El Sawy 2011; Wang et al. 2012). Therefore, studies on what process IT as an important resource of a company takes to improve firm performance need to be consistently made (Tippins and Sohi 2003; Melville et al. 2004; Wang et al. 2012). Second, although previous studies managed to show that integrative information technology (IT) has a positive impact on SCI, what could be the consequences of integrative supply chain strategy has not been clearly described yet. An integrative supply chain strategy is defined as a business process that creates values by integrating not only firms but also suppliers and customers (Stevens 1989; Tan et al. 1998; Vickery et al. 2003). Integrative IT and SCI are the core constituents of an integrative supply chain strategy. Integrative IT is defined as technology that facilitates the collection of vital information concerning key business processes and the sharing of such information across functional areas and across firm boundaries. In other words, integrative IT means IT that enable the achievement of integration both internally and externally. Therefore, this study is aimed at contributing to the achievements of previous studies on the integrative supply chain strategy (Vickery et al. 2003; Prajogo and Olhager 2012) by examining the impact of integrative IT on firm performance. This paper is structured as follows: Section 1 explores the research purpose and need; Section 2 reviews recent literature on theoretical background, integrative supply chain strategy, supply chain integration, and firm performance, and suggests hypotheses; Section 3 explains the research sample and measures; Section 4 presents the results of analysis; and Section 5 summarizes the findings and discusses the research implications.