ABSTRACT: Malnutrition is one of the major causes of illness among infants in Nigeria and this result from poor weaning practice as a result of high cost of commercial weaning foods available. The nutritional composition, mineral composition and growth response of blended infants and weaning foods made from the combinations of crayfish, maize and millet grains were investigated. The blended diet was made by blending powdered maize and millet grains which sorted for stones, pebbles and other physical defects with crayfish that had been sorted to remove stones and other unwanted particles such as hard bones and fish fingerlings and were dry-milled. Fifty (50) weaning laboratory rats were purchased from the animal colony of the Department of Physiology, Ladoke Akintola University of Technology, Ogbomoso, Oyo State, Nigeria for the purpose of this study. Their weights and ages were noted. The rats were acclimatized and fed with normal diets for seven days before distribution into five groups of ten rats in each cage. On the last day of the experiment, the weight of the rats were recorded, the rats were dissected and the quality of protein in the blended diets was evaluated by estimating the Protein Efficiency Ratio (PER) and Food Efficiency Ratio (FER). The compositions of mineral available in the blended diets were quantified using an atomic absorption spectrophotometer (AAS). The composition of nutrients in blended infant diets were estimated using standard method. The results of ash, crude fibre, moisture, fat, protein, carbohydrates, vitamin B, Vitamin C and energy kcal/100g ranged from 2.42-2.12; 0.80 - 0.40; 6.88-3.68; 7.4-4.0; 16.00-10.40; 75.00-69.00; 15.70 – 10.00; 1.53 – 1.03 and 415-410kcal/100g respectively. The concentration of sodium, magnesium, potassium, calcium, iron and phosphorus ranged from 32.02 -52.11; 500.09 – 707.78; 397.01 – 657.80; 250.04 – 506.04, 6.80 – 16.12 and 230.45 – 515.00 respectively. The FER and PER obtained from the blended diet ranges from 0.08 – 0.12 and 1.04 – 2.32 respectively. This study indicated that locally made weaning and infants food from grains and crayfish food can meet the nutritional needs of infants. The blended diet shows more superiority in terms of nutritional composition, mineral content and Protein Efficiency Ratio when compared with the commercially available weaning food. This can then play a vital role in producing weaning and infant’s foods that can provide the nutritional needs needed for quality growth and eradicate malnutrition.