Ukrainian volunteer battalions are military, police and paramilitary formations that were formed from volunteers in a response to Russian military intervention in Ukraine. Most of the formations were formed by government agencies: Ministry of Defence and Ministry of Internal Affairs, the minority are independent.
As of September 2014, 37 volunteer battalions took active part in battles of the War in Donbass.
In January 2017 Ukraine's Defense Minister Stepan Poltorak stated that 40 thousand volunteers were fighting for Ukraine.
Since spring 2014, Ministry of Defence had formed 32 territorial defence battalions. At the end of 2014, territorial defence battalions were reorganized as motorized infantry battalions.
Besides territorial defence battalions, several regular units of Armed Forces of Ukraine were formed from volunteers, such as 3rd Airmobile Battalion "Phoenix" or 54th Reconnaissance Battalion "UNSO". In 2015 the 46th Spetsnaz Battalion "Donbas Ukraine" was created from volunteers of Donbas Battalion who decided to switch from National Guard of Ukraine to Armed Forces.
Ministry of Internal Affairs had established 56 special tasks patrol police units sized from company to battalion. After several reorganizations, this number shrunk to 33 units.
The National Guard of Ukraine, subordinated to Ministry of Internal Affairs, had established several reserve battalions, among which were Donbas Battalion and General Kulchytskiy Battalion formed from volunteers and Maidan activists. The Azov Battalion, initially formed as a special task patrol police unit, in October 2014 was moved under National Guard command.