Enterprise organizations' budgetary systems often exist in the behaviors of budgetary slack, which have attracted a great deal of attention. This study investigate the effects of the organizational performance and the customers' relationship quality under the budgetary slack condition of small and medium enterprises (SMEs) in Taiwan by using the different levels of management accounting system. This study collected with 220 valid samples from subjects, who are middle or advanced level managers (higher than assistant managers) in the Changhua County EMBA association in Taiwan, using path analysis and adjusting effect analysis to test our hypotheses. The results of the research indicate: Budgetary slack was significantly associated the customers' relationship quality and organizational performance variables. In addition, Owing to enforcing the customers' relationship quality, the link between budgetary slack and organizational performance will be stronger.