This study investigated the role of timbre for the perception of emotion in instrumental sounds. In 2 experiments, 180 stimuli were created by mixing sounds of 10 instruments (flute, clarinet, trumpet, tuba, piano, French horn, violin, guitar, saxophone, and bell). In Experiment 1a, participants received stimuli 1 at a time and rated the degree to which each stimulus sounded like each of the 10 instruments (i.e., timbre judgment). In Experiment 1b, participants received the same sound stimuli and rated whether these stimuli sounded happy, sad, angry, fearful, and disgusting (i.e., emotion judgment). The authors extracted acoustic features from these instrumental sounds and examined the extent to which these features could predict both emotion and timbre ratings made for the same sound stimuli. Our regression analysis showed that regularity, envelope centroid, sub band 2, and sub band 9 explained timbre and emotion ratings. The relationship between acoustic features and emotion judgments of basic emotions, however, was not uniform. Sub band 7, related to perceived activity in a sound, predicted anger, fear and disgust, but not sadness. Because sub band 7 could predict all emotions except for sadness, this indicates that some timbre-related features play a substantial role in the perception of emotion and that timbre could be a more useful indicator for specific emotions rather than emotion in general.