Cross-cultural investigations addressing the development of individual differences are important because these speak to the generalizability of results and the extent to which the development of temperament and personality differs by culture. The present study was aimed at comparing manifestations of fear, defined in infancy as startle or distress to sudden changes in stimulation (e.g., facial/bodily expressions of fear), and inhibited approach to novelty (e.g., escape/avoidance), for samples from Spain (n = 51) and the United States (n = 102). We obtained data from mothers of U.S. and Spanish infants at 12 months of age, also observing these babies in the context of a structured laboratory procedure designed to elicit fearful reactivity. Data reduction efforts produced coherent observation-based fearfulness constructs for both groups, and individual indicators were also examined. Significant differences between U.S. and Spanish infants for the observation-based fear composite and component indices of distress vocalizations, bodily fear, and escape intensity, but not for the parent-report of this attribute, were demonstrated. A significant culture-by-gender interaction emerged for the laboratory-based fear composite and the intensity of facial fear indicator, wherein Spanish female infants exhibited higher intensity of expression, relative to the U.S. counterparts.