MDB
MDB may refer to:

Computing
.mdb, a file-extension used in certain versions of Microsoft Access databases
MDB, a kernel debugger for the Linux kernel.
MDB, the NASDAQ ticker symbol for MongoDB, a database management system.
Message Driven Bean, a special type of Enterprise JavaBean
Modular Debugger, a debugger available as part of the Solaris Operating System
Multidrop bus, a category of computer bus

Politics
Mitglied des Deutschen Bundestages (MdB), a member of the German Parliament
Brazilian Democratic Movement, a centrist political party in Brazil

Other uses
Multilateral Development Bank
Maidstone Barracks railway station, UK National Rail station code
3,4-methylenedioxybutanphenamine, an entactogenic drug
Medulloblastoma common type of primary brain cancer in children
My Dying Bride, a British doom metal band

See also
1MDB, 1Malaysia Development Berhad, Malaysian strategic development company