The solution deals with the insect trap with an attractant made of a natural substrate. The attractant comprises water, further at least 0.01t% of weight of a vacuum vaporised filtered extract of the natural substrate which was obtained from a food material dissolved by a solvent based on organic solvents or ethanol, and further the attractant comprises at least 0.1% of weight of a detergent, while the attractant is located in at least two bowls of a different colour, whose depth is at least 1 cm and volume of at least 500 ml. This trap allows capture of a wide variety of species of the dipterous insect and its partial preservation, which is particularly advantageous at the qualitative taxonomic and faunistic studies.