In order to meet the enmergency decision-making needs of urban waterlogging and to reduce losses, a urban waterlogging Emergency Group Decision Model based on the TOPSIS method was developed. On the one hand, due to the urban waterlogging occurrence with characteristics of uncertainty, complexity and periodicity, the interval grey number was used to evaluate attributes and weights of indices for the emergency plans needed to evaluation. On the other hand, in order to coordinate the complex relationship between multiple objectives effectively, the TOPSIS method was introduced to evaluate the schemes. After building weighted standardized matrix, use TOPSIS method to determine the program's positive and negative ideal solutions, to calculate the relative proximity, and to comprehensively integrate with decision-maker's authoritative weight and obtain relative proximity of group decision-making, then to rank and select the best plan according to the vector order of possible matrix. By analyzing a particular case, the results indicated that, the method was feasible and practical, which can provid a theoretical reference for the emergency decision of city waterlogging events.