Optical signalling device (1, 20, 30) for vehicles (A), comprising: a support element (2) fitted to the abovementioned vehicle (A), a revolving element (3) arranged on the support element (2) and coupled to drive means (4) able to cause rotation thereof and one or more optical signalling elements (8) associated with the revolving element (3) and electrically connected to an electric power source able to illuminate them. Each optical signalling element (8) comprises one or more laser light generators/emitters (9).