In the era of digitization, creating city image IP is the key to enhance the effect of the city’s external publicity. This paper systematically analyzes the factors influencing the competitiveness of city IP brand and constructs a comprehensive evaluation index system. The method of approximating ideal solution ranking (TOPSIS) is chosen to calculate the distance between city image IP design alternatives and positive and negative ideal solution solutions to find the optimal solution. Using the gray correlation analysis method, the gray correlation of each key index is calculated to mine the key factors of urban image IP optimization. The results show that the weight of the core factor is 0.35, and the weight of tourism resources and urban environment is 0.20. The comprehensive evaluation index of the brand communication effect of each city image IP Di improves from 0.314247 to 0.921435. The grey correlation of the four factors of the first-level index layer is always greater than 0.500, and the standard deviation of the branding factor has the smallest value of 0.58. The comprehensive use of the TOPSIS method and the grey correlation analysis method to find the optimal factors. TOPSIS method and gray correlation analysis can find the optimal city image IP design scheme and effectively improve the city brand communication effect.
