Big-eyed bugs Geocoris spp. (Lygaeidae, Hemiptera) are small insects that is found in many parts of the world. They are beneficial because they eat a multitude of insect pests in agriculture. Big-eyed bugs Geocoris spp. are insects that receive research attention in Florida and elsewhere because of the benefits that this species give to plants (Mead, 2001). Big-eyed bugs reproduce many generations in a year on weeds, perennial crops, bushes. In spring the female big-eyed bugs start laying eggs on the bud, the leaves of the host plant. Understanding the biology and the role of predator Geocoris spp. in ecosystem will provide an alternative method in sustainable agriculture development. In this short review, we discuss some convenient diets for the application of mass rearing Geocoris spp. | Big-eged bugs geocoris: Diets research and potential of use in prevention of a number of insect pests in Vietnam