Detecting and grading the state and evolution of wake turbulence caused by an aircraft is made on the basis of radar signals reflected by this turbulence, these signals being analyzed through analysis cells of given dimension in terms of distance and bearing. A first preliminary detection step detects and locates turbulence in a cell. A second step determines the strength of the detected turbulence, while a third step determines the age of the detected turbulence as well as the geometric parameters which characterize it. This method makes it possible to detect wake turbulence and to determine at one and the same time the position and the strength of the latter as well as its stage of evolution.