This article first elaborates on the characteristics and classification of big data for maritime law enforcement, and analyzes the current application status of big data in the field of maritime law enforcement. Subsequently, based on the research situation of big data application in the marine field both domestically and internationally, discussions were conducted on the direction of big data application towards maritime law enforcement. Finally, in response to the shortcomings in the application of big data for maritime law enforcement, and drawing on existing research experience at home and abroad, a method based on the Apriori algorithm for data mining of maritime illegal activities is proposed.