Business Bank in Indonesia is very attractive and profitable, and it is no wonder, when investors from neighboring countries such as Malaysia and Singapore are interested to buy banks in Indonesia. But when do the acquisition, employees often overlooked aspect, and makes employees nervous and confused and consequently negatively affect overall performance. At the time it changed owners, can definitely be a change vision and mission and ultimately change Organizational Culture. The process of organizational culture change correctly is often forgotten by the new owners of the bank, because it was the focus of the core business is financial business. The process of organizational culture change is not properly managed the process of changing corporate culture, not only resulting in decreased performance, but also increase turnover. The impact of poorly managed organizational culture change process, the optimality of the ROI is not running as fast as expected by the new owner. Thus the process of changing the corporate culture must be managed properly and systematically.