Given to the flammability and combustibility of liquefied petroleum gas, especially to its safety risk during producing, storing and transporting, this article for one thing launched in-depth analysis on a number of LPG spherical tank accidents in the past, then introduce a general description of LPG spherical tanks of a oil gas processing plant, where the author belongs. In order to undertake assessment on the danger the explosion of LPG spherical tanks, this article employed commonly-used UVCE explosion theory to carry out calculations on the hazard radius launched by the explosive energy of several LPG spherical tanks of distinct reserves. Besides, a preliminary analysis as well as a risk assessment was figured out via the calculation results. Finally, our paper's conclusion was presented and a set of preventing and controlling management measures were submitted in terms of the running of equipment and technique, the assisting system and workers' operations according to the result of risk assessment.