Leaders of Bulgaria, Czech Republic, Slovakia, Hungary, Estonia, Latvia and Lithuania are also expected to participate in the event.
NATO members agreed in February to establish six command and control units in Bulgaria, Estonia, Latvia, Lithuania, Poland, and Romania to facilitate rapid deployment of a Very High Readiness Joint Task Force.
Romania will also host a new deployable Multinational Division Headquarters for the southeast. Poland will station a similar center for the northeast.
Russia warned that an increase in NATO forces near its border is provocative and a threat to regional and global stability.
The Bucharest meeting will precede a July 2016 NATO summit of all member country heads of state and government, in Warsaw.