This study examined the structural validity of scores from the Batería III Woodcock-Munoz Pruebas de Habilidades Cognitivas (Batería III COG), the Spanish-language version of the Woodcock-Johnson III Tests of Cognitive Abilities (WJ III COG) among 164 children ages 5-12 living in the Peruvian Amazon. Exploratory factor analyses were used in the preliminary investigations. Subsequently, confirmatory factor analysis was utilized in the main analysis. The findings supported both a 4-correlated-factors structure, involving the cognitive domains of Verbal Comprehension, Working Memory, Processing Speed, and Fluid Reasoning, and a bi-factor structure, involving the cognitive domains of Verbal Comprehension, Working Memory, and Processing Speed and one General Intellectual Ability (GIA) factor. Findings from the bi-factor model support the use of the Batería III COG as a measure of GIA in this region but not necessarily as a measure of all hypothesized cognitive subdomains, which were largely subsumed into the GIA factor. Results confirm previous findings that g predominates in the factor structure of scores produced by WJ III COG tests. Further implications for use of the Batería III COG in the Amazon region are discussed.