An apparatus for the inactivation and fine filtration of viruses and microorganisms in an air flow comprising a high-voltage power supply and, in series along the air flow: an air flow pretreatment means formed of oppositely charged current-conductive filtering units (7, 7') with a plate made of a permeable high-porosity insulating material installed between the filtering units; a two-compartment inactivation chamber, each compartment whereof being embodied as a needle corona electrode and a cylinder non-corona electrode arranged coaxially to each other and each being electrically connected to a plate made of a current-conductive filtering material; and a precipitator embodied as oppositely charged plates arranged in parallel to each other and made of a high-porosity current-conductive material, with plates between them made of a permeable high-porosity insulating material, the apparatus being characterized in that: at least the current-conductive filtering unit of the pretreatment means which is first along the air flow is embodied as - a cylinder electrode having a base in the form of a plate made of a permeable porous current-conductive material and positioned adjacent to the plate, which is made of a permeable high-porosity insulating material, - a needle electrode arranged coaxially to the cylinder electrode on the side of the front end thereof, and having its point directed toward the insulating plate, and - a plate, which is made of a high-porosity current-conductive material, positioned in front of, at a distance from and electrically connected to the needle electrode, wherein the cylinder electrode and the needle electrode are connected to the opposite poles of the power supply. an air flow pretreatment means formed of oppositely charged current-conductive filtering units (7, 7') with a plate made of a permeable high-porosity insulating material installed between the filtering units; a two-compartment inactivation chamber, each compartment whereof being embodied as a needle corona electrode and a cylinder non-corona electrode arranged coaxially to each other and each being electrically connected to a plate made of a current-conductive filtering material; and a precipitator embodied as oppositely charged plates arranged in parallel to each other and made of a high-porosity current-conductive material, with plates between them made of a permeable high-porosity insulating material, the apparatus being characterized in that: at least the current-conductive filtering unit of the pretreatment means which is first along the air flow is embodied as - a cylinder electrode having a base in the form of a plate made of a permeable porous current-conductive material and positioned adjacent to the plate, which is made of a permeable high-porosity insulating material, - a needle electrode arranged coaxially to the cylinder electrode on the side of the front end thereof, and having its point directed toward the insulating plate, and - a plate, which is made of a high-porosity current-conductive material, positioned in front of, at a distance from and electrically connected to the needle electrode, wherein the cylinder electrode and the needle electrode are connected to the opposite poles of the power supply. at least the current-conductive filtering unit of the pretreatment means which is first along the air flow is embodied as - a cylinder electrode having a base in the form of a plate made of a permeable porous current-conductive material and positioned adjacent to the plate, which is made of a permeable high-porosity insulating material, - a needle electrode arranged coaxially to the cylinder electrode on the side of the front end thereof, and having its point directed toward the insulating plate, and - a plate, which is made of a high-porosity current-conductive material, positioned in front of, at a distance from and electrically connected to the needle electrode, wherein the cylinder electrode and the needle electrode are connected to the opposite poles of the power supply. - a cylinder electrode having a base in the form of a plate made of a permeable porous current-conductive material and positioned adjacent to the plate, which is made of a permeable high-porosity insulating material, - a needle electrode arranged coaxially to the cylinder electrode on the side of the front end thereof, and having its point directed toward the insulating plate, and - a plate, which is made of a high-porosity current-conductive material, positioned in front of, at a distance from and electrically connected to the needle electrode, wherein the cylinder electrode and the needle electrode are connected to the opposite poles of the power supply.