A soil leaching column experiment was conducted to investigate K leaching from various soils and to reveal the relationship between K leaching and soil properties. The results showed that under the light rain (87 mm), the soil texture was the main factor in determining K leaching for the soils without application of K fertilizer. The lighter the soil texture, the greater the amount of the K leached. While under the heavy rain (435 mm), soil available K was the main factor in determining how much K could be released from the unfertilized soils. When 200 mg/kg K was applied to the soils, both the content of silt fraction and slowly available K (SAK) were the main factors influencing K leaching under the light rain (87 mm). As the content of soil silt or the SAK increased, the K leaching from the soil decreased. But soil total K and SAK were the main factors in determining K leaching under the heavy rain (435 mm). When the rain fall was very higher, the apparent K fertilizer leaching ratio (AKLR) within 2 h was negatively correlated to content of soil silt. However, AKLR within 24 h was negatively correlated to pH, silt, total K, SAK and feldspar content in soils, and the silt and total K content were more closely related to AKLR than other factors.