With petrochemical industry development and actualization of the strategic oil reserve program in China, if fire or explosion happens in crude oil tank area which is one of major hazard installations of this industry, personal casualty and loss of national property will occur, so it is very important to control the distance between crude oil tank area and its surrounding assembly occupancies as well as industrial facilities. Described is the establishment process of calculation model of the regional safety clearance in oil depots, analyzed is the regional safety clearance in an oil depot by applying the calculation model and results obtained from the analysis are consistent with those specified in relative standards, which shows that this model can be applied to analyze effectively the regional safety clearance of oil tank area in plot plan design scheme.