Background and objectives : To elucidate modulators of rapid eating behaviors, behaviors in elderly residents in a nursing home were observed using a video recording methods. Methods : Participants of 17 elderly residents were employed. Durations and numbers of chewing of diets with and without soup were measured. Subjects were divided into the fast-eating group and slow-eating group based on duration of chewing. Relationship between duration of chewing of diets with soup and duration of chewing of diets without soup was analyzed by linear regression. Results : Proportion of duration and numbers of chewing in diets with soup to those of diets without soup in the fast-eating group was lower than those of the slow-eating group. Both of duration and numbers of chewing of diets without soup depended on those of diets with soup ( p =0.001) . Conclusions : Modulators of rapid eating behaviors in elderly residents might be lower duration and numbers of chewing of diets with soup.