The device for the microbiological analysis of a support (41) adapted to contain microorganisms marked by a fluorophore agent comprises illuminating means adapted to illuminate said support (41) comprising two bases (21) on each of which is mounted at least one group of light sources (22), with said sources (22) of that group being regularly spaced from each other to form an array for illuminating said support (41), said bases (21) being fixed to a frame of said device, one on each side of an opening (9) formed in said frame, with said bases (21) being inclined towards each other in the direction of a predetermined location for reception of said support (41) in said device.