The digital thread (DT), a new paradigm for the development of complex engineering systems, has garnered widespread attention in recent years. The DT serves as a key driver and game-changer for the digital transformation of engineering systems due to its advantages in promoting the collaboration of stakeholders to aid decision-making. This study provides a systematic and quantitative survey of publications about the DT. By using bibliometric analysis tools, current progress on the DT in the engineering domain is visually identified. We analyzed the distribution of research teams, professional publishing sources, current research topics, and future research trends, revealing that current research of DT emphasizes the features of lifecycle, integration, interoperability, and decision-making inspired by the data-information-knowledge-wisdom (DIKW) model. Through a systematic review of relevant publications from the perspective of these key features, we propose an enabling framework of the DT, including the concept, reference architecture, and “3I” enabling technologies (integration; interoperability; and intelligent decision technologies). Finally, we outline the current challenges faced by the DT in the engineering domain, including issues about integration challenges, professional workforce, and cost analysis. This study aims to facilitate a more comprehensive understanding of the current states and research directions of the DT in the engineering domain.