The invention discloses a method for optimizing the data transmission latency in communication of an intelligent power grid, belonging to the field of data transmission of intelligent power grids. Different types of data can be optimized by introduction of corresponding different virtual latencies; in combination with the arrival time and the corresponding deadline of a data packet thereof, a virtual timestamp is obtained; the scheduling sequence thereof is dynamically adjusted; the more sensitive the latency is, the shorter the virtual latency thereof is; even the practical timestamp of the data packet thereof is not changed, the virtual timestamp is changed by the virtual latency; therefore, on one hand, a data packet having the sensitive latency is superior to a data packet having the non-sensitive latency; on the other hand, due to introduction of the virtual latency, the Domino phenomenon is also solved; and thus, on the premise that the latency non-sensitive data is not influenced, the latency performance of the latency sensitive data is improved.