With the advent of data-driven cyber physical systems (DDCPS), there has been a fundamental shift in the way computers interact with the physical environment In this section, we begin by elucidating the concepts of data integration and fusion of DDCPS. Subsequently, we provide an overview of the various methods employed for data fusion, which can be categorized into three groups: stage-based, semantic-based, and artificial intelligence-based approaches. These techniques emphasize the fusion of knowledge rather than mere pattern mapping and data, distinguishing them from the conventional data integration methods in database research. Then, case studies of cloud-integrated cyber physical systems (CPS) for smart cities and big data fusion framework for smart healthcare are proposed. Finally, the existing challenges of CPS data integration and fusion are summarized, and future research directions are discussed.