Abstract: The temperature of oil product will increase when transporting in pipeline system, which is mainly caused by pumps' operatioin, restriction devices and fluid flowing along the undulated pipelines. The temperature increment in the transportation period is extremely harzadous to light-end products, especially when throughput rate increases, which makes the oil products transported loss, quality of the oil products degrade and environment pollute, and even more the severe heat stress yields on pipeline induced by temperature increment. These problems must be considered in the design and operation of oil products pipeline. An analysis on the mechanism of temperature increment of oil products has been made, the equations for the temperature increment of oil products have also been given respectively. The calculated results show a good approach to measured results on the basis of a oil products pipeline case.