Abstract: Aiming at the problem of signal collaborative control at multiple intersections in the transportation network, a semi distributed three-layer architecture was used to segment the transportation network, and a traffic signal collaborative optimization model was established based on the dynamic characteristics of vehicle flow. In order to solve the problem of offset conflicts between intersections, a hierarchical strategy was proposed to achieve the optimal configuration of offset. In addition, an immune based fireworks algorithm was proposed based on the characteristics of the built model, which accelerated the convergence speed of the algorithm, avoided falling into local optimum, and improved the global search ability and solution accuracy of the algorithm. Experimental analysis showed that the proposed model, algorithm, and hierarchical strategy had certain advantages in solving the problems of signal collaborative control and offset conflict at multiple intersections.