Background: To assess the serum alkaline phosphatase in oral and oropharyngeal cancer and its association with clinicopathological characteristics. Materials & methods: A total of 100 subjects with confirmed diagnosis of oropharyngeal carcinoma were enrolled. Another set of 100 healthy controls were included. Diagnosis of oropharyngeal carcinoma was done on the basis of histopathological findings. Staging was done according to the Union for International Cancer Control classification. Evaluation of preoperative fasting blood ALP activity was done. 5 mL fasting venous blood was collected from antecubital vein of study and control group and ALP levels were measured using spectrophotometer. All the results were recorded and analysed using SPSS software. Results: Mean ALP levels among the patients of oropharyngeal carcinoma group and control group were 142.3 IU/L and 78.1 IU/L respectively. While comparing the results statistically, significant results were obtained. Mean ALP levels among males and females of the oropharyngeal carcinoma group were 141.8 IU/L and 143.7 IU/L respectively (p-value > 0.05). Mean ALP levels among patients of oropharyngeal carcinoma group with Tumour size T1 + T2 (<4cm) and tumour size T3 + T4 (> 4 cm) were 121.3 IU/L and 151.8 IU/L respectively (p-value < 0.05).Mean ALP levels among patients of oropharyngeal carcinoma group with early and advanced tumour stage were 123.8 IU/L and 149.6 IU/L respectively (p-value < 0.05). Mean ALP levels among patients of oropharyngeal carcinoma group with and without bone involvement were 146.2 IU/L and 131.7 IU/L respectively (p-value < 0.05). Conclusion: Alkaline phosphates could be considered a sensitive marker for the detection of cancerous lesions.