Soil organic carbon can affect soil potassium by affecting the release of soil mineral potassium and the characteristics of potassium dissolving bacteria. Therefore, in this paper, based on the long-term positioning experiment of rice straw mulching and vetiver hedgerow to control soil and water loss in red soil slope farmland, by comparing conventional management (CK), rice straw mulching (S), rice straw mulching and vetiver hedgerow (S+V), the effects of rice straw mulching and vetiver hedgerow measures on soil main chemical properties were studied, and the distribution of soil aggregates and the distribution of carbon and potassium in soil aggregates were analyzed. The results showed that soil pH, organic carbon, total potassium and available potassium were significantly higher under S+V than CK and S, compared with CK, which were increased by 0.23 units, 6.52%, 11.60% and 11.49% respectively. No significant difference was found in the distribution of soil aggregates under different treatments, and the proportion of soil aggregates >0.25 mm was the highest among all soil aggregate components. Compared with CK, the organic carbon content of >2 mm soil aggregates were increased by 9.42% and 40.03% under S and S+V, respectively, meanwhile, the contents of total potassium in soil aggregates and >2 mm, 0.25-0.053 mm and <0.053 mm were increased by 3.67%, 4.92% and 5.14%, and the contents of available potassium in soil aggregates >2 mm and <0.053 mm were increased by 20.10% and 12.28% under S+V, respectively. Therefore, on the red soil slope farmland, the combined measures of straw mulching and vetiver hedgerow are effective soil conservation measures to improve carbon and potassium distribution of soil aggregate components, which improved organic carbon content of >2 mm soil aggregates and significantly increased available potassium content of >2 mm and <0.053 mm soil aggregates, thus is conducive to maintaining soil structure and ensuring high yield of crops.