In an effort to develop novel mushroom-derived anti-obesity nutraceuticals, water and ethanol extracts containing the lipaseinhibitory compound from Phellinus linteus were prepared, and their nutritional components were determined. The optimal conditions for the extraction of P. linteus lipase inhibitor involved the treatment of the fruiting bodies with distilled water at $80^{circ}C$ for 72 hr and 80% ethanol at $100^{circ}C$ for 60 hr, respectively. The distilled water extract and ethanol extract contained 10.9% and 6.11% of crude protein, and 0.96% and 15.86% of crude fat, respectively. Additionally, the distilled water extract contained a large quantity of minerals, including 239.5 mg of K, 39.3 mg of Mg, and 39.3 mg of Na. The free amino acid content of the distilled water extracts was also higher than that of the ethanol extracts, and in particular, the distilled water extracts contained 5,139 mg of asparagine, 3,891 mg of tryptophan, 2,598 mg of alanine, and 2,066 mg of serine in 100 g of the distilled water extracts. 100 g of the distilled water and ethanol extracts were found to contain 12.31 g and 8.16 g of malic acid, respectively.