Rats were maintained for 30 to 76 days on a purified diet containing 20% fat as hydrogenated cottonseed oil, corn oil, or coconut oil and then injected intravenously with a tracer dose of cholesterol-4-C14. In the 6 days following injection higher excretion of C14 was observed in animals maintained on hydrogenated cottonseed oil. Of the activity extracted by petroleum ether after saponification, a lower percentage was present in the digitonin-precipitable fraction in animals fed coconut oil. Smaller amounts of cholesterol were excreted by the coconut oil-fed rats. No consistent differences were observed in total C14 activity of various organs of the different dietary groups at any time period. Neither serum cholesterol nor serum C14 activity was affected by variation of the type of dietary fat given these rats.