A method for controlling directly and in real time positioning of a biological element on a zone of a support, in which the biological element is labeled with a tracer that emits a light radiation and the zone of the support is located in a layer of a material capable of trapping the light radiation. The biological element is positioned on the zone of the support. The intensity of the light radiation trapped in the layer is measured. The positioning of the biological element is determined by comparing the intensity thus measured with at least one reference value. The above operations can be carried out successively or simultaneously. A device can apply the method to the positioning of one or more biological elements on one or more zones of a support.