With respect to the security issue of storage tanks’ seal ring fire, by taking 10×104 m3 crude oil tank as the research object, using Visual C++ 6.0 programming software to calculate the model domain of seal ring fire and FLUENT programming software, the thermal radiation of burning storage tank was simulated, which could get the thermal radiation in different distance from the burning storage tank and the damage to people and devices in different thermal radiation. The results showed that the burning storage tank radiated heat equably to all around under the condition of breezeless and steady pool fire. With the distance from the burning storage tank increasing, the thermal radiation decreased. When the thermal radiation decreased from 37.5 kW/m2 decreasing to 12.5 kW/m2, the damage to people and devices greatly decreased. Without considering the influence of wind speed and the adjoining storage tanks’ spraying, the safe distance of adjoining storage tank was 35.5 m.