Lean Manufacturing Practices And Their Effect On Sustainability Performance: Insight From Selangor Manufacturing Industry Tan Woei Xiang Department of Production and Operations Management, Faculty of Technology Management and Business, Universiti Tun Hussein Onn Malaysia, 86400 Batu Pahat, Johor, Malaysia. woeixiang1997@gmail.com Norasmiha Mohd Nor Department of Production and Operations Management, Faculty of Technology Management and Business, Universiti Tun Hussein Onn Malaysia, 86400 Batu Pahat, Johor, Malaysia. asmiha@uthm.edu.my Abstract Lean manufacturing practices benefited to firm performance, however the research regarding the implementation of lean manufacturing on firm sustainability performance is limited. Therefore, the aims of the study are to examine the effect of lean manufacturing practices towards firm sustainability performance using Triple-Bottom Line (TBL) approach. The same lean manufacturing practices was adopted from Norani and Wahab (2011) as indicator in the study. Data were gathered by using questionnaire and was sent to 308 manufacturing industry located in Selangor and 25 industry experts by email. By the way, there were only 51 responses returned. Statistical Package for Social Sciences (SPSS) 22.0 system is applied to answer the research objectives and to test the hypotheses. The findings show process and equipment, and customer relationship has significant influence on TBL sustainability performance whereas manufacturing planning and control, human resources and supplier relationship show the opposite. The present study contributes to practitioner in research perspective and beneficial to manufacturer the extent level of lean manufacturing practices and it effect on TBL sustainability performance in order to help their firm achieve sustainable improvement in economic, environmental and social aspects. Keywords Lean Manufacturing Practices, Sustainability Performance, Triple-Bottom Line, Manufacturing Sector 1. Introduction Manufacturing sector in Malaysia have been set as a core sector for Malaysia economic growth. The report showed contribution of manufacturing sector to Gross Domestic Product (GDP) in Tenth Malaysia Plan have achieved RM 1,111 billion (Department of Statistic Malaysia, 2020). Moreover, 2.8 million of new job opportunities have created by manufacturing sector to new employment. Also, the sales value of Malaysia manufacturing has growth up to RM 76.1 billion in December 2019 which increased 22.1 per cent as compare to RM 72.3 billion in 2018 at same period (Department of Statistic Malaysia, 2020). Nonetheless, the contribution of manufacturing sector in national account (GDP) at current prices showed ranked at second place after services sector as compare to 2015 prices which ranked at first places. This due to rapid changes and highly competitive between manufacturing industries and others sector, therefore sustainability performance become significant important nowadays for a firm to survive in marketplace and lead to purpose of conducted this study by implemented Lean Manufacturing Practices (LMPs) as indicator. Proceedings of the 11th Annual International Conference on Industrial Engineering and Operations Management Singapore, March 7-11, 2021 © IEOM Society International 5315