Foreign labors are important to Taiwan¡¦s manufacturing industries as most of them are taking 3D (Dirty, Dangerous, and Difficult) jobs or night shifts. Previous researches have put attention on the influences of human resource management (HRM) practices on foreign labors¡¦ adaptability or job performance. There is comparatively lesser researches focus on the mediating and moderating variables between foreigner labors¡¦ HRM practices and their performance. Based on the framework of hierarchical HRM, this study aims to explore the mediating effect of foreign worker readiness and the moderating effect of agent involvement on the relationship between foreign labor HRM practices and their job performance. Due to lack of empirical researches related to agent¡¦s involvement, hence this study first applied to qualitative research method to explore the construct and create the measurement and then used quantitative research method to examine the hypotheses. According to the data from Kaohsiung city manufacturing enterprises (total 50 sets of samples; including 50 HR heads and 373 foreign workers), the results revealed that: 1. The relationship between HRM practices and foreign labors¡¦ job performance. (1) Training & education practices are positively related to foreign labors¡¦ job performance. (2) Incentive practices are positively related to foreign labors¡¦ job performance. (3) Accommodation management practices are positively related to foreign labors¡¦ job performance. 2. The relationship among HRM practices, foreign labor¡¦s readiness and job performance. (1) Recruitment and selection management practices are positively related to foreign labors¡¦ job readiness. (2) Foreign labors¡¦ job readiness is positively related to their job readiness. (3) Recruitment and selection management practices are positively related to foreign labors¡¦ job performance through their job readiness. 3. The relationship among agent involvement, foreign labor¡¦s HRM practices, foreign labor¡¦s readiness and job performance. (1) Agent involvement positively moderates the relationships between training & education management practices and foreign labors¡¦ job performance. (2) Agent involvement positively moderates the relationships between incentive practices and foreign labors¡¦ job performance Base on these findings, we suggests that practitioners should improve the oversea recruitment and selection practices for promoting foreign labors¡¦ readiness and ensuring their job performance. Practitioners can also strengthen the magnitude of education & training, incentives and accommodation management to promote foreign labors¡¦ performance. For enhancing the management effectiveness, practitioners should work closely with the agent in education & training and incentive practices. For the future researches, we suggest that longitudinal research design could further inspect the causal-effect relationship between HRM practices and performance. Furthermore, researches can also expand the sources of data to enhance the generalizability of the results.