Based on soil radon gas survey in Quanzhou City and Jinjiang City, the authors conducted an investigation of the soil radon gas environment in an area of some 465 km2.  The results indicate that radon gas concentrations in soils of Quanzhou and Jinjiang urban areas are at a lower level, whereas those in soils of Quanzhou and Jinjiang suburbs are at a fairly high level. It seems that the radon gas concentration is mainly related to geological background: radon gas concentrations in soils derived from weathering of adamellite, moyite, and biotite schist are higher than those in soils derived from weathering of other rock types.