Abstract: The invention relates to a system for the forced waving of flags for advertising devices and similar and to the corresponding operation methods. The inventive system comprises a support (10) for supporting a flag or similar (2) with the aid of a flag-waving shaft (20) and for securing blowing means (11) which release forced air flows (S) that are applied to the flag or a similar element disposed on the waving shaft. The aforementioned blowing means (11) supply one or more laminar air flows (S) through the outlet(s) (110) thereof. The flag-waving shaft (20) is positioned perpendicularly to the direction of flow of the laminar air flow(s) on an external side of, and close to, the outlets of the blowing means, said zone containing flows with no turbulence.