In view of the lack of research on the influence between droplets and droplets in the same steam under the natural convection condition of the two vertical droplets in the spray precooling process of LNG tank. Based on the energy conservation principle of gas-liquid interface, the natural convection evaporation and heat transfer characteristics of double droplets under different temperature differences, particle sizes and relative distances were analyzed by using computational fluid dynamics ( CFD ) method. The results are as follows : ① The heat flux, heat transfer and mass evaporation rate of droplet surface increase linearly with the increase of temperature difference from 10 K to 190 K. ② The heat flux on the droplet surface decreases rapidly at first and then decreases slowly with the increase of particle size from 0.1 mm to 2.5 mm, and the heat exchange rate and mass evaporation rate increase rapidly with the increase of particle size. ③ The heat flux, heat exchange rate and mass evaporation rate on the upper droplet surface remained basically unchanged with the increase of relative distance from 10 to 70, while those on the lower droplet surface increased slowly with the increase of relative distance from 10 to 70. ④ The increase rates of heat flux, heat exchange rate and mass evaporation rate of the lower droplet ratio decrease with the increase of temperature difference, slowly increase with the increase of particle size, and increase with the increase of relative distance.