Abstract: By indoor soil column simulated method, effects of soil improved by straw on leaching ability of phosphorus and vertical distribution in different soil aggregates were studied, the concentrations of total phosphorus and water-soluble phosphorus in leaching solution, and total phosphorus, Fe-P, Al-P, Ca-P, O-P and water-soluble phosphorous in different soil layers were measured. Results showed that, the total phosphorus leaching of soil improved by different straws decreased. Compared to other treatments, the total phosphorus concentration in leaching solution of carbonized corn straw treatment was less, and carbonized corn straw had significant inhibition on phosphorus leaching loss. Compared to T1 treatment, the cumulative leaching loss of water-soluble phosphorus of T2, T3, T4 treatment decreased by 59.44%, 30.56% and 69.44%, respectively, and there was significant difference between CK and treatments. In the layer of 20 ~25 cm, the increasing value of inorganic phosphorus concentration of T2, T3, T4 treatment was less than T1 treatment, indicating that soil improved by different straws prevented the inorganic phosphorous migration into the lower soil layer.