The accumulative levels of Total petroleum Hydrocarbons (TPH) on agricultural soil around an oil refinery were monitored. Four major sites around the refinery were chosen: east, west, north and south. Experiments were done in two seasons: pre monsoon and post monsoon. The enzymes aryl sulphatase and urease activities were measured to evaluate the effects of TPH on soil biochemical characteristics. Results showed that the study area were soil were contaminated by TPH. Soil TPH and aryl sulphatase activity varied in the sequence west>north>south>east in both the seasons. However, the changes in urease activity showed directional variation in both the seasons. Correlation studies illustrated that at the current pollution level, soil TPH concentration was positively correlated with aryl sulphatase activities. On the contrary, the urease activities showed a significant negative correlation with the TPH concentration. This indicates that soil enzymatic activities could be used as a sensitive biological indicator of petroleum contamination. This study will be supportive to use proper bioremediation technique to detoxify the petroleum contamination for their ultimate removal from the soil.