In order to improve the hydrophobic properties of polyurethane foam (PUF), peanut shell powder (PSP) was firstly modified by hexadecyltrimethoxysilane (HDTMS) to prepare the hydrophobic modified peanut shell powder (H-PSP). The testing results of water contact angle showed that the water contact angle of modified H-PSP was increased from 0° of PSP to 145.2°. Then, PUF loaded with H-PSP composites (H-PSP-PUF-n, n is the mass fraction of H-PSP in polyurethane prepolymer PPU) were prepared by prepolymer method. The structure and properties of H-PSP-PUF-n were characterized and tested. The results showed that the loading of H-PSP on PUF improved the surface roughness and mechanical properties of foams. The optimal loading capacity of H-PSP was optimized to be 10% of the mass of PPU (H-PSP-PUF-10). Compared with PUF, the static water contact angle of H-PSP-PUF-10 reached to 142.4°, which was higher 50.4° than that of PUF. The oil-water separation experiments of dichloromethane, petroleum ether, kerosene, xylene and hexamethylene were carried out. The results showed that the adsorption capacity of H-PSP-PUF-10 for different oils was 7~9 g/g, as well as it had good oil-water selectivity. After 15 cycles of adsorption-desorption, the adsorption capacity of H-PSP-PUF-10 for different oils was about 6.5~8.0 g/g, which had excellent recyclability.