Abstract: The proportion of biopharmaceuticals in the pharmaceutical industry has been increasing gradually. Modern development of biopharmaceuticals place higher demands on product quality and consistency control, with more and more attention to process research. Based on the full understanding of product properties and production processes by R & D and production personnel, process analysis technology (PAT) has been integrated with the concept of quality by design (QbD), which represents the development trend of pharmaceutical industry in the future. In this paper, we expound the latest application of PAT for the production of biological products in the upstream, harvest, downstream and drug production in the biotechnological industry, from the view point of QbD and intelligent manufacturing. The difficulties of PAT application are discussed in microbial fermentation, cell culture, centrifugation, refolding, chromatography, formulation, filling and lyophilization, with the challenges and prospects for PAT application.