* Albania: The G36C is used in limited numbers by specialized units.
* Australia: Australian Federal Police (G36C).[8]
* Belgium: Used by the Antwerp local police special squad BBT (Bijzondere Bijstandsteam).[9]
* Brazil: Brazilian Federal Police (G36K).[10]
* Canada: Used by the Victoria Police Department.
* Croatia: Limited numbers in use with certain specialized army and police units.[11]
* Estonia: Used in small numbers by select units.
* Finland: Finnish Border Guard rapid response units.
* France: French GIGN and RAID.
* Germany: Standard service rifle of the Bundeswehr (G36 or G36A1, G36A2, G36K and G36C),[12] Bundespolizei (German Federal Police) and SEKs of the State Police.
* Georgia: Georgian Army special forces, presidential guard.
* Greece: The G36 was evaluated by the Hellenic Army as a potential replacement for the license-produced variant of the G3 rifle currently in service and emerged as the winner of an industry competition. The order would involve 112,370 rifles but acquisition has been postponed.[13]
* Iceland: Icelandic National Police which includes the Víkingasveitin counter-terrorist unit.
* Indonesia: Indonesian Army Kopassus Counter Terrorist Unit Sat-81 Gultor and Indonesian Marine Corps Denjaka (G36C and G36K).
* Italy: Italian Gruppo di Intervento Speciale special operations group of the Carabinieri, Aeronautica Militare for the RIAM Special Forces group, Col Moschin special operation group of the Italian Army.
* Jordan: The Royal Special Forces employ the G36C.
* Latvia: The G36KV is the standard assault rifle of the Latvian Army and Speciālo uzdevumu vienība (Latvian special forces).[14][15]
* Lithuania: Lithuanian Army adopted the G36V and G36KV in 2007.[16]
* Malaysia: Malaysian Army Grup Gerak Khas 11th Counter Terrorist Regiment, Royal Malaysian Police Pasukan Gerakan Khas Counter-terrorist unit (G36C) and Malaysian Maritime Enforcement Agency (G36E).
A Spanish naval boarding team member with a G36E.
Spanish special forces (UOE) personnel on exercise.
* Mexico: Law enforcement agencies such as state, federal and military police as well as the Mexican military. The Army will be getting funds to start building the G36V rifle in 2009 [1]
* The Netherlands: Several police units.
* Norway: Norwegian Navy Kystjegerkommandoen.[14]
* Philippines: Naval Special Warfare Group, Light Reaction Battalion and Presidential Security Group.
* Poland: Used by the Polish police (G36C, G36K), special forces GROM (G36K, G36) and the naval special warfare group FORMOZA (G36KV), Government Protection Bureau (G36K, G36KV and G36C), the Internal Security Agency (G36C) and Central Bureau of Investigation (G36C).
* Portugal: Portuguese Marine Corps, Portuguese National Republican Guard, Portuguese Air Force Polícia Aérea (military police) and NFOT (former-RESCOM).
* Romania: The G36KV is used by several special operations groups such as the 1st Special Operations Battalion and combat divers.
* Singapore: Singaporean STAR unit.
* Slovakia: G36KV and G36C used in small numbers by the Slovak Police's Útvar Osobitného Určenia or "special assignments unit".
* Slovenia: Deployed in small numbers by the Slovenian counter-terrorist unit Specialna Enota Policije.
* Spain: Purchased the G36E to equip all branches of the Spanish Armed Forces. 75,219 units acquired with deliveries starting in 1999 and completed in 2005; 60,000 rifles were issued to the Spanish Army, 7,559 were allotted to the Spanish Navy and the Spanish Air Force received a total of 7,660 weapons. Naval G36's are slightly different in that they feature a 3x optical sight. The rifles are manufactured jointly by both Heckler & Koch in Oberndorf am Neckar and the General Dynamics Santa Bárbara Sistemas facility in A Coruña, Spain at a unit cost of €778.99.[17]
* Sweden: Special Forces ( SSG and SIG ) and Nationella insatsstyrkan (National Task Force, NI) (G36C).
* Thailand: Royal Thai Navy SEALs, Royal Thai Marine Corps Recon Battalion (G36C).
* United Kingdom: UKSF and many AFOs including CO19.
* United States:United States Pentagon Police, Baltimore Police Department, Los Angeles Police Department, the Milwaukie, Oregon Police Department, the Cobb County, Georgia Police Department, the Roanoke County, Virginia Police Department SWAT unit, the Jefferson Township, New Jersey Police Department, the Cinnaminson Township, New Jersey Police Department, the St. Louis Police Department, and the Utah Department of Corrections.
* United Nations: Safety and Security Service (mainly G36K)