Abstract: With the advent of the big data age, the influence of big data on manufacturing has become increasingly obvious. It is very important to use the advantage to reasonably transform and upgrade traditional manufacturing. We summarize the definitions of big data in manufacturing. It emphasizes that manufacturing big data comprising volumes of data through the whole value chain can be used to improve intelligent manufacturing, using big data analysis and other technologies. We illustrate three processes in the development and applications of manufacturing big data with examples. Afterwards, we analyze the effects on value chain from five aspects in detail:research and design, supply, production, marketing, and post-sales service, which reflects the transformation trend from production-driven to demand-driven. Finally, we analyze the challenges faced by manufacturing big data from three perspectives:big data storage, big data analysis technologies, and big data safety and privacy, and propose the prospects for Chinese traditional manufacturing.