The invention relates to a time delay analysis method of Wireless HART network end-to-end data transmission in a smart power grid, and belongs to the technical field of smart power grids. The method comprises the following steps: mapping each transmission channel into a processor, thereby mapping a data flow into tasks executed on multiple processors; analyzing the time delay caused by the channel competition in data flow end-to-end transmission and the time delay caused by transmission conflict according to a scheduling algorithm, comparing the time delay with deadline of the data flow so as to fast determine the schedulability of each data flow and provide evidence for the network optimization.