Abraraw Chane (PhD)Winta Hailu2025-07-302025-07-302024-10https://etd.aau.edu.et/handle/123456789/5720This study investigates the relationship between leadership style and organizational cultureand how they influence worker performance. Leadership is about providing direction and vision for a team to work toward common goals, and then to encourage and assist each teammember in achieving those goals. Organizational cultures, on the other hand, refer to the shared attitudes, values, and beliefs that influence how business is conducted within acompany. Both have the potential to have a substantial impact on employee performance and, consequently, the success of any business. In the fast-paced word of architecture success ofan organization usually depends on employee performance. This study examines the relationship between employee performance, organizational culture, and leadership styles atarchitecture firms in Addis Abeba. The study used secondary data (books, papers, literature, publications, and journals) as well as primary data obtained from employee of architecturecompanies using regular questionnaires. The researcher used convenience sampling to identify eight architectural firms for the case study because of time constraints. The surveywas distributed and collected from different professionals working in design departments in the selected eight firms. Out of the 60 surveys distributed, 49 were correctly completed,yielding an 82% response rate. The questionnaires were analyzed using IBM SPSS statistics version 29.02, through inferential and descriptive analysis. The study's findings indicate thatthere is no single, well-defined leadership style within these companies. Nonetheless, the researcher was able to recognize the most prominent or related kind of leadership style byobserving specific trends in companies. The inferential study revealed a positive correlation between organizational culture and employee performance in transformational anddemocratic leadership styles. According to the study's findings, the importance of having suitable leadership and organizational behavior is obvious because it has a significantimpact on employee performance. The research of these eight organizations found that the majority of them do not have an organized or planned leadership system. As a result, it isrecommended that a leader or manager open their mind to learning about different types of leadership and organizational cultures, and then adopt the one that is most fit for theircompany. Furthermore, based on the study's findings, it is recommended that a company adopt a transformational leadership style in order to develop an innovativeorganizational culture and thereby improve employee performance. Keywords: Leadership style, organizational culture, employee performance, transformationalleadership style, architectural firms in Addis Abebaen-USThesis