Background: The role of oxygen free radicals in the initiation, promotion and progression of carcinogenesis and the protective role of anti-oxidant defenses have been the subject of much speculation in the recent past with confl icting reports in the literature. Objectives: The aim of this study was to measure the concentration/levels of serum total proteins, albumin and advanced oxidation protein products as markers of oxidative stress in sera of patients with an oral pre-cancerous lesion and frank oral cancer. Materials and methods: The study consisted of sera analysis of 30 new patients of histologically proven well-differentiated, oral squamous cell carcinoma and 10 patients, clinically diagnosed with a potentially malignant epithelial lesion, speckled leukoplakia, aged between 40 to 60 years, in addition to 25 healthy controls. One way analyses of variance were used to test the difference between groups. The normality of data was checked before the statistical analysis was performed. Results: The study revealed variations in sera levels of albumin and advanced oxidation protein products to be statistically signifi cant (p < 0.001). Conclusion: The results obtained emphasize the need for more studies with larger sample sizes to be conducted before a conclusive role could be drawn in favour of sera levels of total protein, albumin and advanced oxidation protein products as markers of diagnostic signifi cance and of the transition from the various oral pre-cancerous lesions and conditions into frank oral cancers.