A pot experiment was conducted to investigate effects of biochar produced from corn cobs on some chemical properties and potassium status in a calcareous sandy soil. The addition of biochar to this soil resulted in significant increases (P ≤ 0.05) in the soil pH, organic matter (OM), soluble potassium, and available potassium. The soil potential buffering capacity of potassium (PBCK) significantly increased with adding the biochar to the calcareous sandy soil. Significant increases were also occurred in the activity ratio of potassium at equilibrium (ARK eÞ with the applying the biochar to this soil. Moreover, biochar additions gave significant increases in the labile pool of K ð Þ ΔKo value of the calcareous sandy soil. The fresh and dry weight as well as potassium content of wheat plants grown in the calcareous sandy soil significantly increased with biochar additions.