The objective of this study was to estimate the losses of potassium in the laboratory by large leaching soil columns containing disturbed soils. Results are as follows: Potassium moves quickly in the latosol. There are K~ which deriving from potassium fertilizer in the leachate at 20 cm depth after irrigating30 mm water;Concentration of K~ in the leachate at 60 cm depth are descending with the time growing and positively related to the fertilizer quantity applied after 39 days; Concentration of K~ in the leachate at 120 cm depth ascends with the fertilizer quantity applied after 45 days

and the movement velocity of potassium in the test is about 2.7 cm/d. Accumulation leaching amount of at 120 cm depth are positively related with the fertilizer quantity applied and their leaching ratio is 3.28%. Using equation lnY_t=a blnt can describe the relation between the accumulation leaching amount of K~ with time at 120 cm depth with different potassium fertilizer quantity applied.