This study aims to examine the factors that influence corporate decision-making factors in transactions with Sharia Bank in Indonesia and recommend strategies to increase corporate customers in Islamic banking to increase their market share considering that corporate customers have large purchase power parity. This study was conducted to fill the research gap where it will be analyzed how the factors that influence the decisions of corporate customers in Indonesia in transacting with Islamic banking. The sample in this study is financial decisionmakers in corporations consisting of the CEO, CFO, Head of Finance, Vice President Finance, and GM Finance. Sampling in this study used the Slovin formula with a target sample of 394 respondents, both Muslim and non-Muslim. The results of this study indicate that in general the level of knowledge of sharia from both Muslim and non-Muslim respondents is still minimal for basic muamalah fiqh knowledge. From the results of the analysis, it was found that the variables of service quality and sharia compliance affect the reputation of Sharia Bank in Indonesia, where the reputation of Sharia Bank is the only variable that directly affects the decisions of corporate decision-makers in transactions with Sharia Bank. Meanwhile, the variables of religiosity, sharia knowledge, the role of company shareholders do not have a positive influence on the dependent variable. Finally, this study recommends the management of Sharia Bank to determine strategic steps to improve reputation as the most decisive variable for a company to transact with Sharia Bank. Reputation is enhanced by improving service quality and sharia compliance