Employee performance remains a challenge for companies because of the increasingly competitive level of competition. Organizations are increasingly required to focus on Human Resource Management (HRM) to improve organizational sustainability. Achieving organizational sustainability becomes unrealistic without employee participation and commitment. This study aims to analyze the effect of work-life balance, job demands, job insecurity on employee performance with employee well-being as a mediating variable. The research method used is explanatory quantitative with SEM-PLS. The sample in this study were 100 employees of PT Jaya Lautan Global. The sampling technique used in this research is saturated sampling (census). The results showed that Work-Life Balance and Job Demands had a positive and significant effect on Employee Well-Being. Job Insecurity has a negative and significant effect on Employee Well-Being. Work-life balance has a positive and significant effect on employee performance. Job Demands have a negative and significant effect on employee performance, while Job Insecurity has a negative and insignificant effect on employee performance. Employee well-being has a positive and significant effect on employee performance. The results of the mediation show that employee well-being can partially mediate the effect of work-life balance and job insecurity on employee performance, while employee well-being can fully mediate the effect of job demands on employee performance.