Integrated Assessment Models (IAMs) for climate change represent a frontier research field in climate economics. By integrating the economic system and the climate system, IAMs enable the direct comparison of the costs and benefits of climate change responses on a unified platform.Based on a comprehensive introduction to the basic concepts, development history, current research status, research hotspots, key issues of climate change integrated assessment models, and typical existing IAMs, Climate Change Integrated Assessment Model and Its Applications focuses on the China's Climate Change Integrated Assessment Model (C3IAM), which is independently designed and developed by the BIT Center for Energy and Environmental Policy Research (CEEP-BIT). The book systematically describes its methodology and overall framework, analyzes the basic structure, core equations and typical application cases of each component module one by one, and provides a dedicated explanation of the coupling modes between different C3IAM modules and the processing of socio-economic data. As a typical application of the C3IAM model, the book proposes strategies and pathways for global climate change mitigation.