Abstract: In order to solve the problem of unstructured, heterogeneous, and difficult to share accident cases, and to improve the utilization rate of accident cases in emergency rescue management, this paper uses network crawler technology to obtain a large number of real-time accident cases published on the Internet by local regulatory authorities.The framework method constructs a data structure to express the knowledge contained in accident cases, and establishes a universal, comprehensive and shared dynamic database of accident cases; on the basis of accident case database, a new case retrieval algorithm is initially proposed, using the index technology as search engine to retrieve unstructured case data. At the same time, the traditional method of case similarity calculation is used to match structured data, and realize the efficient screening of unstructured case data with a small amount of key information, so that the system can be based on the wishes of the commander combining unstructured data and structured data, a focused and inclination case search was carried out. Taking China Coal Mine Safety Production Network as an example to automatically crawl gas, flood, and fire accident cases. The practical results show that this case retrieval process and algorithm improve the effectiveness and practicability of case retrieval.