Severe protein-energy maJnuLrition during infancy is closely related to physical growth and mental development. Very few reports mention the e JTects on motor development of mildly to moderately malnourished infants. Ou r s tudy w-as conducted to clarify the relationship between malnutrition and motor development during infancy. We examined 1,065 chi ldren at Posyandu (Intregated SeJvices Posts) in North Sumatera, Indonesia. Motor development, such as silting and wallcing, was s ignificantly more delayed in malnourished children than in well-nourished children . Parachute reaction showed no significant dillerences between well-nourished and malnourished children. Parachute reaction is a very simple technique and can differentiate between children with cerebral. palsy and malnourished children unable to walk. It might be one of the most appropriate technologies for use at the primary care level. (Paediatr Indones 1998; 38:29-37)