Provided is a method and a device for generating a precoding matrix in a wireless communication system. The method for generating the precoding matrix comprises a step of receiving from a terminal feedback including information on the error angle θ of channel direction information (CDI), which indicates the direction of a channel direction vector, and a step of generating the precoding matrix based on the information on the error angle θ of the CDI, wherein the error angle θ of the CDI indicates the angle between the channel direction vector and a quantized channel direction vector, and includes at least one of a channel quantization error component, a channel feedback delay error component, and a channel estimation error component.