The purpose of this paper is to investigate the impact of ABC（Activity-Based Costing） implementation which has on the behavior of constituent members of an organization, through analysis of customer-specific cost behaviors after ABC has been adopted. Specifically, this paper examines the structural changes caused by the implementation of ABC, using the financial archival data provided by Japanese wholesale company; Iida Co., Ltd.. This study finds that stickiness of customer-specific cost mitigates in the period of which ABC information has come to wide use throughout the company. In addition, cost stickiness mitigates and the cost adjustment is promptly accelerated in response to the sales decrease as far as the customer generating losses are concerned.