Conventional 3 cm entomological radars have been successfully used for many years to observe the migratory flight of the larger insect species, but the range at which these radars can detect individual small insects is limited to a few hundred metres. This paper outlines the design and application of an 8.8 mm wavelength radar to study the flight of insects weighing only 2 mg. Detection ranges in excess of 1 km were achieved for individual insects, and estimates of aerial density made by the radar were found to be within 50% of those made by an aerial sampling device.