The purpose of this paper is to investigate factors affecting the success of lean implementation in Thai logistics companies. Data was collected from the logistic companies implemented lean. Questionnaire survey was used to collect the data. Factor analysis and multiple regression analysis were conducted to understand the relationship between these factors and lean implementation success. The results of this study highlight the importance of leadership and management, financial capabilities, and organization culture as the critical success factors of lean implementation. The results also provide practitioners with guidelines in implementing lean more efficiently and effectively for enhancing their capability and competitiveness towards globalized market.