[Objective] This paper explores the research progress of the process-level semantic representation of experimental protocols. It aims to discover the key issues to be addressed and identify development trends. [Coverage] We used related topics to retrieve the relevant literature from Web of Science, arXiv, Engineering Village, CNKI, Wanfang, and VIP. We also examined the requirements of the submission requirements and evaluation principles of renowned journals on experimental protocols. [Methods] First, we defined the concepts of experimental protocols and their semantic representation at the process-level. Then, we examined the representation methods, representation element extraction, and application of representative data. [Results] The research on process-level semantic representation is in the early development stages. The representation framework was not unified, and the elements were different. The experimental protocols were mainly written in natural language, which were difficult to extract the representation elements automatically. Some studies explored the application of process-level semantic representation data, which leaves more knowledge gaps to be filled. [Limitations] This paper does not thoroughly discuss the technical details of extracting representation elements from literature and data application methods. [Conclusions] We need to establish a unified representation framework for more complete elements by integrating various representation methods. We should also explore automatic extraction methods based on advanced intelligent technology and application using the process-level semantic representation data.