This scoping review examined research trends in the use of the NCAST Feeding Scale, an objective and reliable measure of mother-infant interaction, based on the methodological framework of Arksey and O’Malley. Three databases were searched for studies published through January 2026, and 48 studies were included. Since its development, the scale has been used mainly in intervention and observational studies, most of which were conducted in the United States, where it was originally developed. Participants included both general mother-infant dyads and dyads with health-related risks. The scale was primarily used to evaluate interventions promoting positive mother-infant interaction and to identify infant, maternal, and environmental factors associated with interaction in various feeding contexts. These findings suggest that future studies in Korea should apply the scale to diverse mother-infant dyads, examine related factors, and develop interventions to enhance positive mother-infant interaction.