The Diamondback moth (DBM), Plutella xillostella (Linnaeus) (Lepidoptera: Plutellidae) is the insect pest damaging cabbage in Ukraine, especially in the Southern region. Biology, damage, population dynamics of diamondback moth and effect of natural enemies on the level of infestation of this pest by parasitoids and pathogens were studied in 2004-2007 in the laboratory and field conditions. Obtained results show that in general the pest has 2-3 generations, although up to 5-6 can evolve in the South. Fecundity and life longevity of Diamondback were studied on white cabbage, red cabbage, broccoli, cauliflower and two basic weeds: shepherd's purse and wild mustard. The host plant affects fecundity and life span of the diamondback moth. Fecundity differs significantly and is highest with white cabbage. Fauna of Diamondback moth parasitoids is quite rich. All stages are affected by numerous parasitoids and predators. Around 22 parasitoid species were recorded during the study. Overall parasitism ranged from 18% to 60% varying essentially between the areas. Apanteles (Cotesia) sp., Diadegma sp., Trichogramma sp. were most common in all areas. Steinernema sp., entomopathogenic nematodes are found to be natural enemies of diamondback moth. The range of natural enemies contributes significantly to the control of Diamondback moth. Conservation and augmentation of natural enemies should be used in IPM systems in order to control diamondback moth on cabbage. Entomopathogenic nematodes are prominent biocontrol agents.