An improvised fighting vehicle is an ad hoc combat vehicle resulting from modified or upgraded civilian or military non-combat vehicle, often constructed and employed by civilian insurgents, terrorists, rebels, mobsters, guerrillas, partisans, drug cartels, criminal organizations or other forms of non-state militias and irregular armies. Such modifications usually consist of grafting improvised armour plating and fixed crew-served weapons such as heavy machine guns or antiaircraft autocannons mounted onto the back of a utility vehicle or pickup truck.
Various militias and official militaries have improvised such vehicles ever since the introduction of the first automobiles into military service. During the 1910s and 1920s, the absence of a doctrine for the military use of automobiles or of an industry dedicated to producing them led to a great deal of improvisation in the creation of early armored cars and similar vehicles.