Based on the sensing network to implement the fire emergency escape path planning. Unlike other planning methods, this paper uses grid technology to consider factors such as the impact of crowd density on travel time, smoke diffusion, and the upper limit of space/aisle accommodation. At the time of the fire, the evacuation path planning problem at each location is transformed into the optimization. In the model, a balanced evacuation was considered to achieve the goal of evacuation of the crowd. In the paper, the simulated annealing algorithm was used to solve the optimization model and the experimental results were verified.