This paper attempts to demonstrate the important linkage between human resource development (HRD) and internal marketing (IM) to achieve the organizational effectiveness (OE), and it aims to highlight the effect of human resource development strategies on organizational effectiveness with the mediating role of internal marketing practices. We explore the effects of human resource developments, internal customer satisfaction and commitment and organizational effectiveness. This paper is conceptual and the approach adopted is analytical. Extant research and concepts have been used to develop propositions and to discuss both research and managerial implications, and as a result, first of all, the present paper reviews the relevant literature about IM, HRM and the link between IM and HRD. The study has found that internal marketing strongly supports the relationship between HRD and organizational effectiveness and the satisfaction of internal customers influences customer satisfaction and loyalty before affecting the profitability and growth of the company. Based on research findings, insightfully this study suggested leveraging human resource development to enhance organizational performance.