Poor complementary feeding practices are associated with stunting and growth faltering throughout the developing world. The objective was to compare the effect of using peanut-/soy-based fortified spread (FS) and corn porridge fortified with fish powder (FP) as complementary foods on growth in rural Malawian children. A total of 240 children were enrolled at the age of 6 mo and randomized to receive FS or FP. Both complementary foods provided 836 kJ/d from 6 to 9 mo of age and 1254 kJ/d from 9 to 18 mo of age. Children were followed monthly for anthropometry and fortnightly for the symptoms of fever, cough, or diarrhea until they were 18 mo old. Zn and Se status were assessed at 6 and 12 mo. The primary outcomes were the rates of weight and length gain from 6-12 mo and from 12-18 mo. Children who received FS gained 110 g more (95% CI 220 to 10) from 6-12 mo of age than children receiving FP. Weight gain did not differ between children receiving FS and FP between 12 and 18 mo of age, nor did statural growth from 6 to 12 mo or 12 to 18 mo. A total of 23% of all children were Zn deficient at 6 mo of age and this increased to 37% at 12 mo of age. Neither FS nor FP was associated with significantly improved Zn status. FS was associated with better weight gain from 6-12 mo of age and may be useful in conjunction with additional interventions to improve infant growth in the developing world.