The method and the device find application in farming for biological plant protection from harmful insects. They increase the yield in mass cultivation of the predatory bug, the feeding specialization to the Colorado beetle is preserved, inbreeding is prevented, the genetic variety and vitality are preserved and cannibalism is reduced to a minimum. The mechanical dosing, feeding and collection of eggs prevents any traumatization. By the method one-age eggs are placed in boxes for mass propagation on foam rubber band, synthetic polyamide fibres and folded paper bands, soaked in water. After the larvae for feeding get into 2nd age, anaesthetized caterpillars of the European grain moth are placed. The foam rubber bands are soaked in artificial nutrient and the larvae are fed daily every 4 hours, the newly hatched bugs staying in their abode 2 days (48 hours) and then are moved to new boxes in the form of parallelepipeds positioned on specific places on table tops by means of fixing elements and guiding limiting
