Langerhans cells are dendritic, antigen-presenting cells which reside within the stratified squamous epithelium of skin and various mucosae, where they function as the outermost arm of the immune system. Langerhans cells play an important role in inflammation and immune responses, including anti-tumour activity. Thus this study is aimed to identify the role of Langerhans cell in oral dysplastic epithelium and oral squamous cell carcinoma. Quantitative analysis of Langerhans cells were done in normal oral mucosa (n=10), oral dysplastic epithelium (n=20) and oral squamous cell carcinoma (n=20) with immunohistochemical analysis using monoclonal antibody against CD1a. Counting was done in ten non-overlapping consecutive high power fields by two independent observers. An increase in the number of Langerhans cells were observed from normal mucosa to oral dysplastic epithelium and oral squamous cell carcinoma. There was no statistically significant increase observed from oral dysplastic epithelium to oral squamous cell carcinoma. The immune system responds to the dysplastic and invading epithelium in oral squamous cell carcinoma by recruiting Langerhans cells. Langerhans cells present altered antigen to naïve T cells, thus initiating an immune response. However, tumour microenvironment has a critical role in modulating the recruitment and function of Langerhans cells in oral squamous cell carcinoma