A polyurethane composition is provided. The polyurethane composition comprises (A) one or more prepolymers prepared by reacting at least one isocyanate compound with a first polyol component; and (B) a second polyol component; wherein at least one of the first polyol component and the second polyol component comprises an ester/ether block copolymer polyol synthesized by reacting a starting material polyether polyol with a C4-C20 lactone. The foamed or non-foamed polyurethane product prepared by using the polyurethane composition can achieve inhibited internal heat buildup, high thermal stability, improved curing speed, light stability, heat stability and superior mechanical strength. A method for preparing the polyurethane composition and a method for improving the performance property of the polyurethane product are also provided.