Because there was few literature in the reciprocities between the core organiations(CPA firms) and the other organizations(their customers), we created the organization trust model between the CPA firms and their customers according to the related literature to understand that "CPA firms should have what kinds of characteristics if they want to gain the trust from their customers; and what will happen if they really gain the trust from their customers." We gained the result to test the model by sending the questionnaires to the managers of the accounting department, and we are looking forward to providing all the CPA firms for the reference of management.