Grain-size distbution of the red earth of the Huangjin profile (HJ) and Shahe profile (SH) was measured in the southern Jiangxi Province. The results showed that: 1) grain-size distributions of two red earth sections in the Gannan region are very similar; and 2) the vertical change curve for magnetic susceptibility, Kd and weathering coefficient shows a rmarkable correlation. The particle distribution and particle parameters are correlated, indicating the existence of six cycles of depositional alternation with the pedogenic process in the Gannan red earth, accordingly there are six cycles of climate change.