This study aimed to determine the Usefulness of Accounting Information System for Effective Organizational Performance of Zameco 1 in Palauig, Zambales. The respondents were composed of the total population of 25 Zameco 1 employees. The survey questionnaire method was used in data gathering. The findings show that majority of the respondents belong to the age group from 31-40 years old, most were females and married, believers of Roman Catholic, designated in finance department, has other position not included in the identified choices, with master’s degree professional education, and were in service for 5-9 years. The respondents strongly agree on the usefulness of accounting information system for effective organizational performance. The respondents likewise strongly agree on the impact of accounting information system on organizational financial performance and performance management respectively. There is no significant difference on the level of usefulness of Accounting Information System for effective organizational performance when grouped according to profile variables. There is no significant difference on the impact of accounting information system on the organizational financial performance when grouped according to the respondents’ profile variables. There is a significant difference on the impact of accounting information system on the organizational performance management when grouped according to the respondents’ civil status. And there is a moderate significant relationship between the accounting information system and organizational performance in terms of financial and management.