The present invention relates to a method and device for transmitting and receiving CSI (Channel State Information). A CSI transmission method at a CoMP (Coordinated Multi-Point) device includes steps of receiving a CSI-RS (Reference Signal) from a plurality of transmission points, acquiring an optimal phase difference value causing an optimal channel quality between the plurality of transmission points, based on the CSI-RS, acquiring a CQI (Channel Quality Indicator), based on the optimal phase difference value, and transmitting the CSI including the CQI. According to an embodiment of the present invention, efficient CSI transmission/reception method and device can be provided in a CoMP system.