In the recent work environment, any firm or organization can’t guarantee the achievement of its strategic goals, that is, its success without utilizing IT well, so the IT became the object of main attention, and the reliance on the IT gets more intensified in all business fields. Therefore, each firm and public institute take enormous efforts for setting their internal audit systems appropriate for the recent business environment. Especially as the Public Audit Act began to take in effect from 2010, its raised the necessity to develop a new internal audit administration meeting a more advanced internal audit body’s role and its status as well as the changes in the administration different from the past administration. Reflecting the past, the existing internal audit activities have done around the post-exposure approaching to the known risks or a kind of fragmentary checkup around samples. Besides, the existing internal audits have focused on pointing out the organization’s problems and controlling them. So the organization being audited did not fully accept the internal audit results and there were also some aspects not meeting the internal customer’s needs. Therefore this study aimed to propose an improved model of audit information system supporting the recent audit trends (enhancing the efficiency of work process and consulting) in order to draw out a more strategic improvement plan after analyzing the status quo of public firms’ internal audits and their problems through the review of existing studies and literature about the theme.