With the increase of uncertainty in the construction environment of industrial internet engineering, emergency response capability has gradually become an important factor in ensuring the successful implementation of engineering projects. In order to improve the emergency response ability of industrial internet engineering supply chain, considering the interactive relationships between entities, the game relationship among emergency response entities of industrial internet engineering supply chain is studied in the construction stage of industrial internet engineering projects. A fusion evolutionary game model is established to reveal the integration mechanism of emergency response entities of industrial internet engineering supply chain. The simulation results show that the interest connection of industrial internet engineering supply chain enterprises is the key driving force for the integration of emergency response entities. Mutual benefit, reciprocity and mutual trust serve as the prerequisite basis of successful integration. When the continuous intergration profit increment and income subsidies of participating enterprises outweigh the impact of phased integration strategies adopted by other enterprises on the chain, participants will choose continuous integration strategies regardless of the initial intention of enterprises. Conversely, the evolutionary results will diverge. Understanding the mechanism of emergency response integration and incentivizing active participation of emergency response entities in integration can improve emergency response efficiency and emergency response capacities, ensuring the stability of the supply chain and facilitating the successful implementation of industrial internet project construction.