The urban lifeline Natech event is a multi-risk and multi-subject coupling system. To qualitatively and quantitatively identify the risk conduction chain of urban lifeline Natech events, first, the risk conduction mechanism was analyzed. Urban lifeline Natech events have both natural disaster chains and domino effects. Then, the complexity and dynamic characteristics of the risk conduction chain were analyzed, and a CN-SD model for the risk conduction chain of the urban lifeline Natech event was constructed. Finally, using the text data of "Top Ten Natural Disasters in China" and their reports, CN indicators such as risk path, risk aggregation, and risk conduction were quantified, and SD indicators such as risk correlation and urban lifeline vulnerability were quantified to numerically simulate the risk conduction rate and degree of urban lifeline Natech event. The results show that the model can qualitatively and quantitatively analyze the risk conduction chain of urban lifeline Natech event, and can visualize the dynamic curves of the domino effect risk conduction rate and degree of technical accidents in transportation, electricity, communication, water supply under natural disaster chain scenarios.