Emotional suppression (ES) is a critical component of the ability to self-regulate emotion. However, people who chronically use ES as a primary strategy often experience heightened anxiety or depression. Although functional neuroimaging studies have extensively mapped the brain regions involving in emotional regulation, the neural substrates of ES as a trait construct remain relatively unexplored. Using a validated backward masked facial affect paradigm, we examined the association between ES and functional brain responses to masked angry, fearful, and happy faces. Healthy adults underwent functional MRI and completed the Courtauld Emotional Control Scale as a measure of ES. Correlations between self-reported ES and brain responses to the facial affect stimuli (affective>neutral) were evaluated within the brain regions involved in emotional processing, including the amygdala, insula, anterior cingulate cortex, medial prefrontal cortex, and orbitofrontal cortex. In response to angry faces, higher trait tendency to suppress anger and anxiety was significantly correlated with increased activation within the rostral anterior cingulate cortex, whereas no correlation was observed for masked happy or fearful faces. This finding suggests that the rostral anterior cingulate cortex contributes to the unconscious suppression of emotional responses to angry facial affect and may play a role in the mediating anatomy of trait ES.