Abstract: The field geological survey on soil vertical profile was carried out in Shijing-Dongtian area of Nan'an City, Fujian Province, and the spatial distribution map of soil thickness in Shijing-Dongtian area of Nan'an City is drawn in accordance with the survey results, indicating its distribution characteristics and main influencing factors in the region. The background values of soil thickness in Shijing-Dongtian working area are 20 cm and 15 cm in general, followed by 35 cm and 10 cm soil thickness background values. The main influencing factors of spatial variability of soil thickness in Fujian coastal areas are soil genesis and ground slope. The more stable the sedimentary environment with less human and natural interference, the thicker the soil layer; the soil thickness is negatively related to the ground slope, which means the steeper the ground slope, the thinner the soil thickness.