198th may refer to:

198th Airlift Squadron flies the C-130 Hercules 198th Battalion (Canadian Buffs), CEF, a unit in the Canadian Expeditionary Force during the First World War 198th Division (1st Formation) (People's Republic of China), a military formation of the People's Volunteer Army during the Korean War 198th (East Lancashire) Brigade, a First World War infantry brigade of the British Army 198th Infantry Brigade, was first formed as part of the United States Army Reserve's 99th Division

See also AD 198, the year 198 (CXCVIII) of the Julian calendar