The invention relates to a thermoplastic polyurethane composition and a preparation method thereof. The composition comprises the following substances by the mass percentage: (a) 55-90% of a thermoplastic polyurethane elastomer, (b) 7-40% of a copolymer, and (c) 2-8% of a compatilizer. The copolymer is selected from one or more of the following polymers: SBS, SEBS, SIS and SEPS with the number-average molecular weight of 50 thousand-100 thousand. In addition, EPDM with the weight-average molecular weight of 100 thousand-400 thousand can be added and can cooperate with the copolymer, and in the premise of relatively low copolymer amount, better extinction effect is achieved. According to the ASTM D523 standard, the surface glossiness of the angle of 60 degrees is tested to be less than 10 Gs, and the lowest reaches 0; and the material has good mechanical properties and processing performance, and is suitable for preparation of wire cables, pipes, belts and thin film products.