Abstract: A decontamination liquid spraying appliance has a storage container for the receiving decontamination liquid, in particular of GD5 solution, and further has a spraying device flow-connected to the storage container. The appliance is used for the decontamination of objects contaminated by harmful substances. The storage container is a pressure container with a threaded orifice formed in it. The spraying device contains an adapter head that can be screwed in a pressure tight manner into the threaded orifice and which carries a regulating valve for regulating the quantity of the decontamination liquid to be sprayed. The spraying device further has a hand-actuated air pump that has a pump tube projecting into the pressure container and a pump piston displaceable in the pump tube through a piston rod led through the adapter head, in order to act upon the interior of the pressure container with overpressure.