The invention relates to an extensible light shield driven by a memory alloy for GEO laser communication, and belongs to the technical field of space laser communication. The invention brings forward an extensible light shield driven by a memory alloy for GEO laser communication. The light shield employs multiple independent extensible structures driven by the memory alloy, and during emission, the extensible structures are collected so that the shield external envelope dimension is reduced; and after liftoff, the extensible structures can be automatically extended or collected along with change of a solar irradiation angle, and thus a temperature rise of an optical system, caused by sunlight irradiation is inhibited. The structure of the extensible light shield does not require an external power source and a rotation mechanism, can realize automatic extension and collection of an extensible sun shield, at the same time, can automatically adjust the state of the sun shield according to the irradiation direction of the sun, and guarantees that the sun shield facing the fun is always at an extension state so as to shield sunshine and the sun shield at the back of the sun is always at a collected state so as to prevent the sunshine from being irradiated to the inner wall of the light shield. The method provided by the invention, while ensuring the shielding and heat control effects of the light shield for the sunshine, can effectively improve the reliability of the extensible light shield, reduce the weight and power consumption and improve the availability the extensible light shield.