This volume constitutes the refereed proceedings of the four workshops held at the 30th International Conference on Database and Expert Systems Applications, DEXA 2019, held in Linz, Austria, in August 2019: The 10th International Workshop on Biological Knowledge Discovery from Data, BIOKDD 2019,   the 3rd International Workshop on Cyber-Security and Functional Safety in Cyber-Physical Systems, IWCFS 2019, the 1st International Workshop on Machine Learning and Knowledge Graphs, MLKgraphs2019, and the 16th International Workshop on Technologies for Information Retrieval, TIR 2019.The 26 selected papers discuss a range of topics including: knowledge discovery, biological data, cyber security, cyber-physical system, machine learning, knowledge graphs, information retriever, data base, and artificial intelligent.