Abstract: Arthropods are the most dominant and biodiverse components of terrestrial ecosystemsand have important roles in its functioning. From those, epigeic arthropod biodiversity can be anindicator of soil quality and are usually studied using pitfall trapping. Among insects,coleopterans are the group best represented and soil beetles may play important roles in theecosystem through their activities as predators, herbivores and scavengers. The objective of thiswork was the study of the abundance and diversity of soil coleopterans in organic olive groves.The work took place in two organic olive groves – Cedães and Valbom dos Figos – located nearof Mirandela (Northeast of Portugal) both conducted with natural vegetation in the soil. BetweenApril to November in Cedães and from May to October 2010 in Valbom dos Figos, five pitfalltraps with 9cm of height and 7cm of diameter, filled with ethanol, water and detergent werecollected weekly. In the laboratory the number of beetles was counted and taxonomicallyclassified up to the level of family and then, each specimen was separated by morphospecies. Inboth olive groves, a total of 1202 beetles were collected, 781 in Cedães and 421 in Valbom dosFigos. Cedães grove showed a higher family richness (21) being Carabidae (41.36%),Staphylinidae (24.07%) and Tenebrionidae (15.36%) the most abundant, while in Valbom dosFigos grove the family richness was lower (14) being Carabidae (52.49%), Anthicidae (18.05%)and Staphylinidae (8.31%) the most abundant. This was the first step to characterize thecoleopteran community of organic olive groves from Trás-os-Montes region and this informationwill be explored in order to develope conservation biocontrol schemes that encourage greatercoleopteran biodiversity and to increase their role as biological control agents.