The research aimed to determine the effectiveness of compost containing humic and fulvic acids, and pure humic and fulvic acids in increasing of Ultisol soil chemical properties. The research design used a randomized block design (RBD), consisting of 10 treatments, namely K0: 0 g polybag-1, KO1: 500 g polybag-1, KO2: 500 g polybag-1, KO3: 500 g polybag-1, KO4: 500 g polybag-1, KO5: 500 g polybag-1, KO6: 500 g polybag-1, KO7: 500 g of polybags-1, H: 50 g of polybag-1, A: 500 g polybag-1. Each

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... atment was repeated three times and obtained 30 treatment units. The results showed that pH H2O (K0: 4.49, KO1: 5.64, KO2: 5.47, KO3: 5.43, KO4: 5.51, KO5: 5.39, KO6: 5.48, KO7: 6.17, H: 5.06, F: 5.15), total-N (%) (K0: 0.13, KO1: 0.17, KO2: 0.18, KO3: 0.30, KO4: 0.25, KO5: 0.24, KO6: 0.29, KO7: 0.36, H: 0.16, F: 0.14), organic-C (%) (K0: 1.85, KO1; 2.30, KO2: 2.24, KO3: 2.33, KO4: 2.62, KO5: 2.25, KO6: 2.27, KO7: 2.95, H: 2.32, F: 2.26) , available-P (%) (K0: 2.75, KO1: 3.24, KO2: 3.16, KO3: 3.27, KO4: 3.57, KO5: 3.31, KO6: 3.37, KO7: 3.89, H: 3.10, F: 3.12), exchangeable-Al (me100g-1) (K0: 2.51, KO1: 2.11, KO2: 2.13, KO3: 2.15, KO4: 1.88, KO5: 2.14, KO6: 2.12, KO7: 1.75, H: 2.16, F: 2.17), base saturation (%) (K0: 30.91, KO1: 63.48, KO2: 52.63, KO3: 53.76, KO4: 56.13, KO5: 54.96, KO6: 56.71, KO7: 65.53, H: 39.11, F: 42.76), cation exchange capacity (me100g-1) (K0: 12.76, KO1: 15.64, KO2: 14.86, KO3: 14.35, KO4: 14.13, KO5: 15.01, KO6: 15.50, KO7: 17.94, H: 14.19, F: 13.73). The combined compost treatment of three types of organic matter (Imperata cylindrica + Rice straw + Glincidia sepium) is more effective in increasing the pH, H2O as 37.42%, total-N as 176.92%, Organic-C as 59.46%, available-P as 41.45%, base saturation as 65.53%, cation exchange capacity as 17.94% and exchangeable -Al, Alreduction as 30.28% of ultisol soil. KEY WORDS: compost, humic acid, fulvate, soil chemical, ultisol