The effects of undernutrition on motor coordination and performance of 139 4.0-6.5 year-old Senegalese children were studied. The sample was partitioned into three nutritional history groups: 54 children exposed chronically to a mild-to-moderate form of undernutrition (group A), 52 children hospitalized for severe undernutrition during infancy and nutritionally rehabilitated but who had been subsequently exposed to moderate undernutrition (group B); and 33 children from well-off urban households (group C). Tests included six items from the McCarthy (arm coordination) and the Charlop-Atwell (gross motor coordination) scales, and five motor fitness items (endurance run, shuttle run, distance throw, standing long jump, grip strength). Performances improved with age, and boys performed better than girls in all motor fitness tests except the jump, but not in motor coordination items. In general, group C performed better than group A and B in most of the tests. Body dimensions explained a significant part of variance of motor performance, and stature was the main predictor. After removing the effect of age and body size, differences between nutritional groups disappeared in motor performance, but persisted in certain motor coordination items. It is concluded that chronic undernutrition reflected by reduced body size and perhaps muscle mass is an important determinant of the motor performance of preschool Senegalese children.