This randomized controlled trial aimed to quantify the effects of choir singing on emotional state and anxiety levels of singers. Salivary amylase, PANAS (Positive and Negative Affect Schedule) and STAI-s/-t(State-Trait Anxiety Inventory) were applied before and after a 1-hour single choir session for an experimental group (n = 35) and unstructured time for control group (n = 35). Amylase decreased in the experimental group but increased in the control group (p > 0.05 for F_group; p = 0.014 for F_testbygroup). Follow-up analysis showed this interaction to be due to baseline differences between the two groups. Negative affect decreased in the experimental group and increased in the control group (p > 0.05 for F_test and F_group; p = 0.006 for F_{test by group}). A decrease in positive affect was found between the pre- and post-test for the control group (p = 0.023 for F_test; p = 0.004 for F_{test by group}). State anxiety decreased in the experimental group and increased in the control group (p > 0.05 for F_test and F_group; p = 0.001 for F_{test by group}). Singing in a choir was found to have a positive impact on psychological indicators of affect and anxiety, however, its physiological effect could not be shown using salivary amylase in this study.