Milk samples were collected throughout lactation from 10 captive red-necked wallabies. 2. The milk solids content increased throughout lactation and was accompanied by major changes in the relative proportions of protein, lipid and carbohydrate. 3. The carbohydrate fraction consisted of oligosaccharides in the first half of lactation but changed subsequently to monosaccharides. 4. The quantitative and qualitative changes observed were similar to those recorded for other macropodids.