The invention relates to a device for generating a cold, HF-excited plasma under atmospheric pressure conditions, comprising a metal housing functioning as a grounded electrode in the region of the emergent plasma, wherein an HF generator, an HF resonance coil having a closed ferrite core suitable for the high frequency, an insulating body acting as a gas nozzle, and a high-voltage electrode mounted in the insulating body are disposed in such a manner that they are permeated or circulated around by process gas. In a preferred embodiment, the device comprises an electrically conductive removable cap comprising a slit or hole in the front region. The invention can be used advantageously for plasma treatment of materials for cosmetic and medical purposes. By integrating the plasma nozzle and required control electronics in a miniaturized handheld device, or by using a short high-voltage cable, the invention allows compliance with the electromagnetic compatibility directives and allows the power loss to be minimized and thus a mobile application to be implemented.