A fast gun holster is disclosed. The fast gun holster comprises a holster body and a connecting base. The holster body comprises a barrel receiver used for containing a gun barrel. An installing plate is hinged to one side of the gun barrel receiver through a reset spring and provided with a trigger limiting mechanism. The trigger limiting mechanism comprises a protrusion and a pressing piece. A clamping groove matched with a trigger is formed in the protrusion. The bottom end of the pressing piece is hinged to the installing plate through a reset spring. An arc part matched with the inner side of a trigger guard is formed on the periphery of the pressing piece.