Resumo: Os formicídeos constituem um dos grupos mais importante de insetos sociais do solo, apontados como potenciais indicadores biológicos da degradação ambiental e fornecedores de informações importantes em planos de manejo e conservação de uma dada região. Assim, objetivou-se com este trabalho inventariar a composição da assembleia de formigas e estabelecer as espécies predominantes, utilizando dois diferentes métodos de coleta (pitfall e isca de sardinha), em ecossistema de savana amazônica. Abstract:The formicidae comprise one of the most important groups of social soil insects, identified as potential biological indicators of environmental degradation, and which provide important information in the management and conservation plans for any given region. The aim of this work therefore, was to inventory the composition of ant assembly and establish the predominant species, using two different collection methods (pitfall trap and sardine bait), in a savannah ecosystem of the Amazon. The ants were collected at six different times from December 2010 to January 2011. There were 12 plots, each 250 m in length, in which there were 10 sampling points spaced 25 m apart. At each point, two collection methods were used: pitfall trap and sardine bait, giving 120 subsamples per method. After collection, the samples were taken to the Aquatic Invertebrate Laboratory of the Centre for Biodiversity (CBIO/UFRR) for sorting, and the specimens placed into bottles containing 70% alcohol for later taxonomic classification. Identification of the formicidae as to species and morphospecies was carried out at the National Research Institute of the Amazon (INPA). All materials were deposited in the invertebrate collection of INPA. It was found that the genera with greater occurrence were Camponotus, Crematogaster and Dorymyrmex, while those with the greatest species richness were Pheidole, Solenopsis and Camponotus. The species Crematogaster abstinens and Camponotus novogranadensis were predominant in the area of savannah under study. This is the first record of Kalathomyrmex emeryi in the State of Roraima. The collections made with pitfall traps were more efficient for evaluating ant richness.