In view of the deficiency of the traditional target threat assessment method that only relies on the static detection and collection data, ignores hesitancy degree of target attribute and intention judgment or preference information of command decision-makers. An intuitionistic fuzzy threat decision-making matrix based on attribute value as detection and collection data of different time and linguistic variables is constructed. A target threat assessment method based on intuitionistic fuzzy VIKOR multi-attribute group decision-making is proposed with totally unknown attribute and decision-maker's weights. Firstly, an intuitionistic fuzzy entropy, which considers not only the deviation of membership degree and non-membership degree but also the hesitancy degree of the target attribute, is employed, and comprehensive attribute weights are obtained based on the entropy weight method and weight coordination coefficient. Then, a method to determine decision-maker weights based on the hesitancy degree and similarity measure is proposed. Finally, the target threat ranking is achieved using the VIKOR multi-attribute group decision-making method which can maximize the group interest and weaken the individual regret. The feasibility of the proposed method is demonstrated through a case study of UAV swarm target threat assessment, and its stability and flexibility are verified by numerical experiments, sensitivity analysis and comparative analysis.