Squamous cell carcinoma (SCC) is one of the most common malignant cancer of the oral cavity encompassing at least 92.8% of all oral malignancies. Despite improved diagnostic and therapeutic methods over the 20 last years, this tumour is still characterized by a high rate of mortality. The latest advances of molecular biological methods have contributed to better understand the mechanisms involved in the oral carcinogenetic process. Deregulation of cell cycle, apoptosis and cell-cell/cell-matrix adhesions are considered the pathways mainly influencing this multistage event and scientific researches over the last decade have been performed in order to investigate the biological diagnostic and prognostic parameters related to these events (i.e. tumour growth markers, markers of tumour suppression and anti-tumour response, angiogenesis markers, markers of tumour invasion and metastatic potential, cell surface markers, intracellular markers, markers derived from arachidonic acid, and enzymatic markers). The aim of the present review was to outline the current knowledge on the role of some of these tumour biological markers in carcinogenesis of oral SCC.