21st Army Corps (Ukraine)The 21st Army Corps is a Corps of the Ukrainian Ground Forces.HistoryThe 21st Army Corps is a military unit formed as part of Ukraine's ongoing defense reforms. These reforms aim to improve command structures and operational readiness amid ongoing conflicts.StructureAs of 2025 the corps structure is as follows:XXI Army Corps* Corps Headquarters** Management** Commandant Platoon* 93rd Mechanized Brigade* 155th Mechanized Brigade* 152nd Jaeger Brigade* 159th Mechanized Brigade* 531st Security Battalion