Mitotic catastrophe (MC) is a form of programmed cell death induced by mitotic process dis-orders,which is very important in tumor prevention,development,and drug resistance.Because rapidly increased data for MC is vigorously promoting the tumor-related biomedical and clinical study,it is ur-gent for us to develop a professional and comprehensive database to curate MC-related data.Mitotic Ca-tastrophe Database (MCDB) consists of 1214 genes/proteins and 5014 compounds collected and organized from more than 8000 research articles.Also,MCDB defines the confidence level,classification criteria,and uniform naming rules for MC-related data,which greatly improves data reliability and retrieval convenience.Moreover,MCDB develops protein sequence alignment and target prediction func-tions.The former can be used to predict new potential MC-related genes and proteins,and the latter can facilitate the identification of potential target proteins of unknown MC-related compounds.In short,MCDB is such a proprietary,standard,and comprehensive database for MC-relate data that will facilitate the exploration of MC from chemists to biologists in the fields of medicinal chemistry,molecular biology,bioinformatics,oncology and so on.The MCDB is distributed on http://www.combio-lezhang.online/MCDB/index_html/.