Premature infants are reported to have decreased fat absorption. Because of energy requirements and limitation of gastric capacity, new formulae are sought which will provide absorbable and utilizable fats. In the current study fat absorption in L.B.W. infants fed formulae containing combinations of soy oil, corn oil, coconut oil and medium chain triglycerides was studied. Thirty infants 1250 to 1850 grams were divided randomly into three groups and fed one of three formulae for 21 days. Formula A contained fat as 30% soy, 30% corn and 40% medium chain triglycerides; Formula B, 40% soy, 40% corn and 20% coconut; and Formula C, 100% corn. Three day stool collection were marked by use of Red carmine and collected from 5 to 8 and 12 to 15 days of life. Infants on Formula A had the best mean absorption for both periods of 84.6 and 86.7%; B 73.5 and 81.0% and in C the least absorption of 66.6 and 72.4%. Mean blood cholesterol levels in each group were under 100 mg at 21 days of age. Calcium absorption was best in Formula A. No statistical difference for weight, length and head circumference growth was noted and there were no untoward clinical symptoms. Direct absorption of medium chain triglycerides into the portal system may be responsible for the increased fat absorption and could prove advantageous to low birth weight infants.