The main purpose of this research is to find the relationship of role overload (RO), love of money (LOM), empowerment (EMP), and work engagement (WE) on employee performance (EP) in the fast food industry and also to find the mediating effect of happiness (HAP) between RO, LOM, EMP, and WE on employee performance and moderating role of the spirit of work (SOW) on happiness and employee performance (EP). The data was gathered using the online survey method through questionnaires from the employees of fast food restaurants of South Punjab, Pakistan. The sample size was 297. The smartPLS 3 was used to analyze the data. The result findings show that LOM, WE, and HAP have an influence on EP while RO and EMP have no influence on EP. There was a mediating effect of HAP between EMP and EP whereas there was no mediating influence of HAP between RO, LOM, WE, and EP. No moderating role of SOW between HAP and EP was found. This study findings are very useful for manager/owner of the restaurant the increase their employee performance, which leads to firm high performance.