Attentional preference for social stimuli, such as different facial expressions, is an important part of the development of humans' behavioral and emotional health. Infants demonstrate a predilection for faces and tend to sustain visual attention over non-social stimuli immediately after birth and throughout infancy. Infants begin to identify facial expressions and emotions around the age of 6 to 8 months. Studies have shown that the amygdala plays an important role in infants' attentional bias towards faces and fear processing. The goal of this study was to examine how infants’ amygdala mean diffusivity (MD) relates to 8-month facial expression bias. The study included 40 infants (50% males). All infants completed an MRI scan at 2–5 weeks gestation and an eye-tracking assessment at 8 months old. We investigated theassociations between the right and left amygdala MD metrics and the probability of disengagement in control, neutral, happy, and fearful faces towards salient distractors by using multiple linear regression models. The infants were less likely to disengage from fearful faces than from happy, neutral, or control faces. The higher the right amygdala MD metrics, the lower the probability of disengagement from the fearful face was observed (ß = -.058, p = .047) (Figure 1). This study is the first to look at amygdala MD metrics and infants' attentional bias for fearful facial expressions. These findings highlight the role of the amygdala microstructure in modulating attentional processes, which may have implications for emotional regulation and susceptibility to emotional dysregulation later in life.