Guiding accessibility is a principal function of guide sign, which indicates whether the guide signs can guide people to their destinations successfully or not. The authors build an effective model to optimise the guiding accessibility of guide signs with a minimum economic cost. The authors’ work can benefit guide sign setting, and improve the efficiency of the traffic system. Firstly, the authors introduced the representation of the road network, then the accessibility and integrated optimisation of guiding paths are defined. Based on this, an integrated optimisation model is proposed with the optimisation of the guiding path length and the number of guide signs. Then combining with the genetic algorithm, the algorithm is designed to solve the mixed integer linear programming problem. Lastly, Guangzhou Higher Education Center is chosen as the test area. The integrated optimisation of the multiple guiding paths with the destination of Sun Yat-sen University is realised using the proposed model. The experiment results show that the proposed model can realise the integrated optimisation of an unsuccessful guiding path with the minimum economic cost.